path: root/0001-Modernize-WebInputEvent.patch

From ba38c72a21a6ebde6abf8f19c00c5c4423534106 Mon Sep 17 00:00:00 2001
From: Dave Tapuska <dtapuska@chromium.org>
Date: Mon, 6 Jan 2020 23:48:47 +0000
Subject: [PATCH] Modernize WebInputEvent

Reland 547be4072d5ef59ba1eea93aa0ac6a294f1660d7. It was previously
reverted because CFI bot started to fail. That was fixed here:
crrev.com/2708646cd1a812a84200a1db6208732fe20d49b8

Since the class is no longer memcopied between processes we can
use virtuals.
- Add virtual destructor
- Add pure virtual cloning
- Remove memset
- Remove size attribute

BUG=836826
TBR=nasko@chromium.org,bokan@chromium.org,jbroman@chromium.org

Change-Id: I091683184ada8d693c11f8cb7aff9dae3eaf93e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1988849
Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Cr-Commit-Position: refs/heads/master@{#728694}
---
 .../devtools/protocol/input_handler.cc        |  2 +-
 .../renderer_host/input/input_router_impl.cc  |  3 +-
 .../renderer_host/render_widget_targeter.cc   |  2 +-
 .../site_per_process_hit_test_browsertest.cc  |  2 +-
 .../common/input/event_with_latency_info.h    |  3 -
 content/common/input/input_event.cc           |  3 +-
 .../browser/native_web_keyboard_event.h       |  2 +-
 .../renderer/input/input_event_prediction.cc  |  3 +-
 .../input/main_thread_event_queue_unittest.cc | 33 +---------
 .../input/widget_input_handler_manager.cc     |  3 +-
 third_party/blink/common/BUILD.gn             |  1 +
 .../blink/common/input/web_gesture_event.cc   |  4 ++
 .../blink/common/input/web_keyboard_event.cc  | 13 ++++
 .../blink/common/input/web_mouse_event.cc     |  6 +-
 .../common/input/web_mouse_wheel_event.cc     |  4 ++
 .../blink/common/input/web_pointer_event.cc   | 12 ++--
 .../blink/common/input/web_touch_event.cc     |  4 ++
 .../public/common/input/web_gesture_event.h   | 17 +++---
 .../public/common/input/web_input_event.h     | 53 ++++------------
 .../public/common/input/web_keyboard_event.h  | 24 ++++----
 .../public/common/input/web_mouse_event.h     | 31 +++-------
 .../common/input/web_mouse_wheel_event.h      | 60 ++++++-------------
 .../public/common/input/web_pointer_event.h   | 24 ++++----
 .../common/input/web_pointer_properties.h     | 18 ++----
 .../public/common/input/web_touch_event.h     | 22 +++----
 .../public/common/input/web_touch_point.h     | 16 ++---
 .../platform/web_coalesced_input_event.h      |  7 +--
 .../core/events/web_input_event_conversion.cc |  4 +-
 .../exported/web_coalesced_input_event.cc     | 40 -------------
 .../main_thread_scheduler_impl_unittest.cc    |  7 ++-
 .../blink/compositor_thread_event_queue.cc    |  4 +-
 ui/events/blink/event_with_callback.cc        |  2 +-
 .../blink/input_handler_proxy_unittest.cc     |  8 +--
 ui/events/blink/scroll_predictor_unittest.cc  | 10 ++--
 ui/events/blink/web_input_event_traits.cc     | 35 -----------
 ui/events/blink/web_input_event_traits.h      |  8 +--
 36 files changed, 164 insertions(+), 326 deletions(-)
 create mode 100644 third_party/blink/common/input/web_keyboard_event.cc

diff --git a/content/browser/devtools/protocol/input_handler.cc b/content/browser/devtools/protocol/input_handler.cc
index 3d20f3d4d410..c7a95973d938 100644
--- a/content/browser/devtools/protocol/input_handler.cc
+++ b/content/browser/devtools/protocol/input_handler.cc
@@ -672,7 +672,7 @@ void InputHandler::DispatchMouseEvent(
   modifiers |= button_modifiers;
   base::TimeTicks timestamp = GetEventTimeTicks(maybe_timestamp);
 
-  std::unique_ptr<blink::WebMouseEvent, ui::WebInputEventDeleter> mouse_event;
+  std::unique_ptr<blink::WebMouseEvent> mouse_event;
   blink::WebMouseWheelEvent* wheel_event = nullptr;
 
   if (type == blink::WebInputEvent::kMouseWheel) {
diff --git a/content/browser/renderer_host/input/input_router_impl.cc b/content/browser/renderer_host/input/input_router_impl.cc
index 44c32d2368ee..4b3e15112bdb 100644
--- a/content/browser/renderer_host/input/input_router_impl.cc
+++ b/content/browser/renderer_host/input/input_router_impl.cc
@@ -66,8 +66,7 @@ std::unique_ptr<InputEvent> ScaleEvent(const WebInputEvent& event,
         latency_info.ScaledBy(scale));
   }
 
-  return std::make_unique<InputEvent>(ui::WebInputEventTraits::Clone(event),
-                                      latency_info);
+  return std::make_unique<InputEvent>(event.Clone(), latency_info);
 }
 
 }  // namespace
diff --git a/content/browser/renderer_host/render_widget_targeter.cc b/content/browser/renderer_host/render_widget_targeter.cc
index 5171535dbe68..dd2876a5233c 100644
--- a/content/browser/renderer_host/render_widget_targeter.cc
+++ b/content/browser/renderer_host/render_widget_targeter.cc
@@ -106,7 +106,7 @@ RenderWidgetTargeter::TargetingRequest::TargetingRequest(
     const ui::LatencyInfo& latency) {
   this->root_view = std::move(root_view);
   this->location = ComputeEventLocation(event);
-  this->event = ui::WebInputEventTraits::Clone(event);
+  this->event = event.Clone();
   this->latency = latency;
 }
 
diff --git a/content/browser/site_per_process_hit_test_browsertest.cc b/content/browser/site_per_process_hit_test_browsertest.cc
index 228c8cbc9f3e..48cb1ebc744c 100644
--- a/content/browser/site_per_process_hit_test_browsertest.cc
+++ b/content/browser/site_per_process_hit_test_browsertest.cc
@@ -95,7 +95,7 @@ class TestInputEventObserver : public RenderWidgetHost::InputEventObserver {
 
   void OnInputEvent(const blink::WebInputEvent& event) override {
     events_received_.push_back(event.GetType());
-    event_ = ui::WebInputEventTraits::Clone(event);
+    event_ = event.Clone();
   }
 
   const std::vector<InputEventAckSource>& events_acked() {
diff --git a/content/common/input/event_with_latency_info.h b/content/common/input/event_with_latency_info.h
index e61aa653725e..58e8b8ca2de6 100644
--- a/content/common/input/event_with_latency_info.h
+++ b/content/common/input/event_with_latency_info.h
@@ -41,9 +41,6 @@ class EventWithLatencyInfo {
     if (other.event.GetType() != event.GetType())
       return false;
 
-    DCHECK_EQ(sizeof(T), event.size());
-    DCHECK_EQ(sizeof(T), other.event.size());
-
     return ui::CanCoalesce(other.event, event);
   }
 
diff --git a/content/common/input/input_event.cc b/content/common/input/input_event.cc
index 5204dde65a54..4e11e69a36a1 100644
--- a/content/common/input/input_event.cc
+++ b/content/common/input/input_event.cc
@@ -16,8 +16,7 @@ InputEvent::InputEvent(ui::WebScopedInputEvent event,
 
 InputEvent::InputEvent(const blink::WebInputEvent& web_event,
                        const ui::LatencyInfo& latency_info)
-    : web_event(ui::WebInputEventTraits::Clone(web_event)),
-      latency_info(latency_info) {}
+    : web_event(web_event.Clone()), latency_info(latency_info) {}
 
 InputEvent::~InputEvent() {}
 
diff --git a/content/public/browser/native_web_keyboard_event.h b/content/public/browser/native_web_keyboard_event.h
index 7b10a7402d59..8498d45e54b7 100644
--- a/content/public/browser/native_web_keyboard_event.h
+++ b/content/public/browser/native_web_keyboard_event.h
@@ -57,7 +57,7 @@ struct CONTENT_EXPORT NativeWebKeyboardEvent : public blink::WebKeyboardEvent {
 #endif
 
   NativeWebKeyboardEvent(const NativeWebKeyboardEvent& event);
-  ~NativeWebKeyboardEvent();
+  ~NativeWebKeyboardEvent() override;
 
   NativeWebKeyboardEvent& operator=(const NativeWebKeyboardEvent& event);
 
diff --git a/content/renderer/input/input_event_prediction.cc b/content/renderer/input/input_event_prediction.cc
index bd43bcb389e3..b8a79476e80c 100644
--- a/content/renderer/input/input_event_prediction.cc
+++ b/content/renderer/input/input_event_prediction.cc
@@ -168,8 +168,7 @@ void InputEventPrediction::AddPredictedEvents(
       last_event_timestamp_ + mouse_predictor_->MaxPredictionTime();
   bool success = true;
   while (success) {
-    ui::WebScopedInputEvent predicted_event =
-        ui::WebInputEventTraits::Clone(coalesced_event.Event());
+    ui::WebScopedInputEvent predicted_event = coalesced_event.Event().Clone();
     success = false;
     if (predicted_event->GetType() == WebInputEvent::kTouchMove) {
       WebTouchEvent& touch_event =
diff --git a/content/renderer/input/main_thread_event_queue_unittest.cc b/content/renderer/input/main_thread_event_queue_unittest.cc
index 35a467cf9af2..299833e08d7d 100644
--- a/content/renderer/input/main_thread_event_queue_unittest.cc
+++ b/content/renderer/input/main_thread_event_queue_unittest.cc
@@ -5,6 +5,7 @@
 #include <stddef.h>
 
 #include <new>
+#include <tuple>
 #include <utility>
 #include <vector>
 
@@ -197,8 +198,8 @@ class MainThreadEventQueueTest : public testing::Test,
   void HandleEvent(WebInputEvent& event, InputEventAckState ack_result) {
     base::AutoReset<bool> in_handle_event(&handler_callback_->handling_event_,
                                           true);
-    queue_->HandleEvent(ui::WebInputEventTraits::Clone(event),
-                        ui::LatencyInfo(), DISPATCH_TYPE_BLOCKING, ack_result,
+    queue_->HandleEvent(event.Clone(), ui::LatencyInfo(),
+                        DISPATCH_TYPE_BLOCKING, ack_result,
                         handler_callback_->GetCallback());
   }
 
@@ -354,8 +355,6 @@ TEST_F(MainThreadEventQueueTest, NonBlockingWheel) {
   }
 
   {
-    EXPECT_EQ(kEvents[0].size(),
-              handled_tasks_.at(0)->taskAsEvent()->Event().size());
     EXPECT_EQ(kEvents[0].GetType(),
               handled_tasks_.at(0)->taskAsEvent()->Event().GetType());
     const WebMouseWheelEvent* last_wheel_event =
@@ -446,8 +445,6 @@ TEST_F(MainThreadEventQueueTest, NonBlockingTouch) {
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(3u, handled_tasks_.size());
 
-  EXPECT_EQ(kEvents[0].size(),
-            handled_tasks_.at(0)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents[0].GetType(),
             handled_tasks_.at(0)->taskAsEvent()->Event().GetType());
   const WebTouchEvent* last_touch_event = static_cast<const WebTouchEvent*>(
@@ -464,8 +461,6 @@ TEST_F(MainThreadEventQueueTest, NonBlockingTouch) {
     EXPECT_TRUE(Equal(kEvents[0], *coalesced_touch_event));
   }
 
-  EXPECT_EQ(kEvents[1].size(),
-            handled_tasks_.at(1)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents[1].GetType(),
             handled_tasks_.at(1)->taskAsEvent()->Event().GetType());
   last_touch_event = static_cast<const WebTouchEvent*>(
@@ -482,8 +477,6 @@ TEST_F(MainThreadEventQueueTest, NonBlockingTouch) {
     EXPECT_TRUE(Equal(kEvents[1], *coalesced_touch_event));
   }
 
-  EXPECT_EQ(kEvents[2].size(),
-            handled_tasks_.at(1)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents[2].GetType(),
             handled_tasks_.at(2)->taskAsEvent()->Event().GetType());
   last_touch_event = static_cast<const WebTouchEvent*>(
@@ -602,8 +595,6 @@ TEST_F(MainThreadEventQueueTest, InterleavedEvents) {
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(2u, handled_tasks_.size());
   {
-    EXPECT_EQ(kWheelEvents[0].size(),
-              handled_tasks_.at(0)->taskAsEvent()->Event().size());
     EXPECT_EQ(kWheelEvents[0].GetType(),
               handled_tasks_.at(0)->taskAsEvent()->Event().GetType());
     const WebMouseWheelEvent* last_wheel_event =
@@ -618,8 +609,6 @@ TEST_F(MainThreadEventQueueTest, InterleavedEvents) {
     EXPECT_TRUE(Equal(coalesced_event, *last_wheel_event));
   }
   {
-    EXPECT_EQ(kTouchEvents[0].size(),
-              handled_tasks_.at(1)->taskAsEvent()->Event().size());
     EXPECT_EQ(kTouchEvents[0].GetType(),
               handled_tasks_.at(1)->taskAsEvent()->Event().GetType());
     const WebTouchEvent* last_touch_event = static_cast<const WebTouchEvent*>(
@@ -999,8 +988,6 @@ TEST_F(MainThreadEventQueueTest, BlockingTouchesDuringFling) {
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(1u, handled_tasks_.size());
-  EXPECT_EQ(kEvents.size(),
-            handled_tasks_.at(0)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents.GetType(),
             handled_tasks_.at(0)->taskAsEvent()->Event().GetType());
   EXPECT_TRUE(last_touch_start_forced_nonblocking_due_to_fling());
@@ -1020,8 +1007,6 @@ TEST_F(MainThreadEventQueueTest, BlockingTouchesDuringFling) {
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(2u, handled_tasks_.size());
-  EXPECT_EQ(kEvents.size(),
-            handled_tasks_.at(1)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents.GetType(),
             handled_tasks_.at(1)->taskAsEvent()->Event().GetType());
   EXPECT_TRUE(last_touch_start_forced_nonblocking_due_to_fling());
@@ -1040,8 +1025,6 @@ TEST_F(MainThreadEventQueueTest, BlockingTouchesDuringFling) {
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(3u, handled_tasks_.size());
-  EXPECT_EQ(kEvents.size(),
-            handled_tasks_.at(2)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents.GetType(),
             handled_tasks_.at(2)->taskAsEvent()->Event().GetType());
   EXPECT_EQ(kEvents.dispatch_type, WebInputEvent::kBlocking);
@@ -1058,8 +1041,6 @@ TEST_F(MainThreadEventQueueTest, BlockingTouchesDuringFling) {
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(4u, handled_tasks_.size());
-  EXPECT_EQ(kEvents.size(),
-            handled_tasks_.at(3)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents.GetType(),
             handled_tasks_.at(3)->taskAsEvent()->Event().GetType());
   EXPECT_EQ(kEvents.dispatch_type, WebInputEvent::kBlocking);
@@ -1086,8 +1067,6 @@ TEST_F(MainThreadEventQueueTest, BlockingTouchesOutsideFling) {
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(1u, handled_tasks_.size());
-  EXPECT_EQ(kEvents.size(),
-            handled_tasks_.at(0)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents.GetType(),
             handled_tasks_.at(0)->taskAsEvent()->Event().GetType());
   EXPECT_EQ(kEvents.dispatch_type, WebInputEvent::kBlocking);
@@ -1105,8 +1084,6 @@ TEST_F(MainThreadEventQueueTest, BlockingTouchesOutsideFling) {
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(2u, handled_tasks_.size());
-  EXPECT_EQ(kEvents.size(),
-            handled_tasks_.at(1)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents.GetType(),
             handled_tasks_.at(1)->taskAsEvent()->Event().GetType());
   EXPECT_EQ(kEvents.dispatch_type, WebInputEvent::kBlocking);
@@ -1124,8 +1101,6 @@ TEST_F(MainThreadEventQueueTest, BlockingTouchesOutsideFling) {
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(3u, handled_tasks_.size());
-  EXPECT_EQ(kEvents.size(),
-            handled_tasks_.at(2)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents.GetType(),
             handled_tasks_.at(2)->taskAsEvent()->Event().GetType());
   EXPECT_EQ(kEvents.dispatch_type, WebInputEvent::kBlocking);
@@ -1143,8 +1118,6 @@ TEST_F(MainThreadEventQueueTest, BlockingTouchesOutsideFling) {
   EXPECT_FALSE(main_task_runner_->HasPendingTask());
   EXPECT_EQ(0u, event_queue().size());
   EXPECT_EQ(4u, handled_tasks_.size());
-  EXPECT_EQ(kEvents.size(),
-            handled_tasks_.at(3)->taskAsEvent()->Event().size());
   EXPECT_EQ(kEvents.GetType(),
             handled_tasks_.at(3)->taskAsEvent()->Event().GetType());
   EXPECT_EQ(kEvents.dispatch_type, WebInputEvent::kBlocking);
diff --git a/content/renderer/input/widget_input_handler_manager.cc b/content/renderer/input/widget_input_handler_manager.cc
index 21a11e35ece0..eafde289309f 100644
--- a/content/renderer/input/widget_input_handler_manager.cc
+++ b/content/renderer/input/widget_input_handler_manager.cc
@@ -258,8 +258,7 @@ void WidgetInputHandlerManager::GenerateScrollBeginAndSendToMainThread(
   blink::WebGestureEvent scroll_begin =
       ui::ScrollBeginFromScrollUpdate(update_event);
 
-  DispatchNonBlockingEventToMainThread(
-      ui::WebInputEventTraits::Clone(scroll_begin), ui::LatencyInfo());
+  DispatchNonBlockingEventToMainThread(scroll_begin.Clone(), ui::LatencyInfo());
 }
 
 void WidgetInputHandlerManager::SetWhiteListedTouchAction(
diff --git a/third_party/blink/common/BUILD.gn b/third_party/blink/common/BUILD.gn
index 2461000838d2..b003d6e6db93 100644
--- a/third_party/blink/common/BUILD.gn
+++ b/third_party/blink/common/BUILD.gn
@@ -48,6 +48,7 @@ jumbo_source_set("common") {
     "indexeddb/indexeddb_key_range.cc",
     "indexeddb/indexeddb_metadata.cc",
     "input/web_gesture_event.cc",
+    "input/web_keyboard_event.cc",
     "input/web_mouse_event.cc",
     "input/web_mouse_wheel_event.cc",
     "input/web_pointer_event.cc",
diff --git a/third_party/blink/common/input/web_gesture_event.cc b/third_party/blink/common/input/web_gesture_event.cc
index 512cd96b073d..85a0dc6acb0f 100644
--- a/third_party/blink/common/input/web_gesture_event.cc
+++ b/third_party/blink/common/input/web_gesture_event.cc
@@ -6,6 +6,10 @@
 
 namespace blink {
 
+std::unique_ptr<WebInputEvent> WebGestureEvent::Clone() const {
+  return std::make_unique<WebGestureEvent>(*this);
+}
+
 float WebGestureEvent::DeltaXInRootFrame() const {
   if (type_ == WebInputEvent::kGestureScrollBegin)
     return data.scroll_begin.delta_x_hint / frame_scale_;
diff --git a/third_party/blink/common/input/web_keyboard_event.cc b/third_party/blink/common/input/web_keyboard_event.cc
new file mode 100644
index 000000000000..a75be6d05e3b
--- /dev/null
+++ b/third_party/blink/common/input/web_keyboard_event.cc
@@ -0,0 +1,13 @@
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "third_party/blink/public/common/input/web_keyboard_event.h"
+
+namespace blink {
+
+std::unique_ptr<WebInputEvent> WebKeyboardEvent::Clone() const {
+  return std::make_unique<WebKeyboardEvent>(*this);
+}
+
+}  // namespace blink
diff --git a/third_party/blink/common/input/web_mouse_event.cc b/third_party/blink/common/input/web_mouse_event.cc
index 1942ad589062..5057d07b0afc 100644
--- a/third_party/blink/common/input/web_mouse_event.cc
+++ b/third_party/blink/common/input/web_mouse_event.cc
@@ -15,7 +15,7 @@ WebMouseEvent::WebMouseEvent(WebInputEvent::Type type,
                              int modifiers,
                              base::TimeTicks time_stamp,
                              PointerId id_param)
-    : WebInputEvent(sizeof(WebMouseEvent), type, modifiers, time_stamp),
+    : WebInputEvent(type, modifiers, time_stamp),
       WebPointerProperties(id_param,
                            WebPointerProperties::PointerType::kMouse,
                            button_param),
@@ -34,6 +34,10 @@ gfx::PointF WebMouseEvent::PositionInRootFrame() const {
          frame_translate_;
 }
 
+std::unique_ptr<WebInputEvent> WebMouseEvent::Clone() const {
+  return std::make_unique<WebMouseEvent>(*this);
+}
+
 WebMouseEvent WebMouseEvent::FlattenTransform() const {
   WebMouseEvent result = *this;
   result.FlattenTransformSelf();
diff --git a/third_party/blink/common/input/web_mouse_wheel_event.cc b/third_party/blink/common/input/web_mouse_wheel_event.cc
index 7de30cb50a63..eea98f9a5387 100644
--- a/third_party/blink/common/input/web_mouse_wheel_event.cc
+++ b/third_party/blink/common/input/web_mouse_wheel_event.cc
@@ -6,6 +6,10 @@
 
 namespace blink {
 
+std::unique_ptr<WebInputEvent> WebMouseWheelEvent::Clone() const {
+  return std::make_unique<WebMouseWheelEvent>(*this);
+}
+
 float WebMouseWheelEvent::DeltaXInRootFrame() const {
   return delta_x / frame_scale_;
 }
diff --git a/third_party/blink/common/input/web_pointer_event.cc b/third_party/blink/common/input/web_pointer_event.cc
index 3cc2213dcb27..aa09d605a7d0 100644
--- a/third_party/blink/common/input/web_pointer_event.cc
+++ b/third_party/blink/common/input/web_pointer_event.cc
@@ -30,8 +30,7 @@ WebInputEvent::Type PointerEventTypeForTouchPointState(
 
 WebPointerEvent::WebPointerEvent(const WebTouchEvent& touch_event,
                                  const WebTouchPoint& touch_point)
-    : WebInputEvent(sizeof(WebPointerEvent),
-                    PointerEventTypeForTouchPointState(touch_point.state),
+    : WebInputEvent(PointerEventTypeForTouchPointState(touch_point.state),
                     touch_event.GetModifiers(),
                     touch_event.TimeStamp()),
 
@@ -58,10 +57,7 @@ WebPointerEvent::WebPointerEvent(const WebTouchEvent& touch_event,
 
 WebPointerEvent::WebPointerEvent(WebInputEvent::Type type,
                                  const WebMouseEvent& mouse_event)
-    : WebInputEvent(sizeof(WebPointerEvent),
-                    type,
-                    mouse_event.GetModifiers(),
-                    mouse_event.TimeStamp()),
+    : WebInputEvent(type, mouse_event.GetModifiers(), mouse_event.TimeStamp()),
       WebPointerProperties(mouse_event),
       hovering(true),
       width(std::numeric_limits<float>::quiet_NaN()),
@@ -72,6 +68,10 @@ WebPointerEvent::WebPointerEvent(WebInputEvent::Type type,
   SetFrameTranslate(mouse_event.FrameTranslate());
 }
 
+std::unique_ptr<WebInputEvent> WebPointerEvent::Clone() const {
+  return std::make_unique<WebPointerEvent>(*this);
+}
+
 WebPointerEvent WebPointerEvent::CreatePointerCausesUaActionEvent(
     WebPointerProperties::PointerType type,
     base::TimeTicks time_stamp) {
diff --git a/third_party/blink/common/input/web_touch_event.cc b/third_party/blink/common/input/web_touch_event.cc
index ed4904625db1..20a55c26329a 100644
--- a/third_party/blink/common/input/web_touch_event.cc
+++ b/third_party/blink/common/input/web_touch_event.cc
@@ -6,6 +6,10 @@
 
 namespace blink {
 
+std::unique_ptr<WebInputEvent> WebTouchEvent::Clone() const {
+  return std::make_unique<WebTouchEvent>(*this);
+}
+
 WebTouchEvent WebTouchEvent::FlattenTransform() const {
   WebTouchEvent transformed_event = *this;
   for (unsigned i = 0; i < touches_length; ++i) {
diff --git a/third_party/blink/public/common/input/web_gesture_event.h b/third_party/blink/public/common/input/web_gesture_event.h
index 581955550705..947c1b601916 100644
--- a/third_party/blink/public/common/input/web_gesture_event.h
+++ b/third_party/blink/public/common/input/web_gesture_event.h
@@ -26,7 +26,7 @@ class BLINK_COMMON_EXPORT WebGestureEvent : public WebInputEvent {
     kMaxValue = kMomentum,
   };
 
-  bool is_source_touch_event_set_non_blocking;
+  bool is_source_touch_event_set_non_blocking = false;
 
   // The pointer type for the first touch point in the gesture.
   WebPointerProperties::PointerType primary_pointer_type =
@@ -38,7 +38,7 @@ class BLINK_COMMON_EXPORT WebGestureEvent : public WebInputEvent {
   // not released through a touch event (e.g. timer-released gesture events or
   // gesture events with source_device != WebGestureDevice::kTouchscreen), the
   // field contains 0. See crbug.com/618738.
-  uint32_t unique_touch_event_id;
+  uint32_t unique_touch_event_id = 0;
 
   union {
     // Tap information must be set for GestureTap, GestureTapUnconfirmed,
@@ -180,23 +180,24 @@ class BLINK_COMMON_EXPORT WebGestureEvent : public WebInputEvent {
   // Screen coordinate
   gfx::PointF position_in_screen_;
 
-  WebGestureDevice source_device_;
+  WebGestureDevice source_device_ = WebGestureDevice::kUninitialized;
 
  public:
   WebGestureEvent(Type type,
                   int modifiers,
                   base::TimeTicks time_stamp,
                   WebGestureDevice device = WebGestureDevice::kUninitialized)
-      : WebInputEvent(sizeof(WebGestureEvent), type, modifiers, time_stamp),
-        source_device_(device) {}
+      : WebInputEvent(type, modifiers, time_stamp), source_device_(device) {
+    memset(&data, 0, sizeof(data));
+  }
 
-  WebGestureEvent()
-      : WebInputEvent(sizeof(WebGestureEvent)),
-        source_device_(WebGestureDevice::kUninitialized) {}
+  WebGestureEvent() { memset(&data, 0, sizeof(data)); }
 
   const gfx::PointF& PositionInWidget() const { return position_in_widget_; }
   const gfx::PointF& PositionInScreen() const { return position_in_screen_; }
 
+  std::unique_ptr<WebInputEvent> Clone() const override;
+
   void SetPositionInWidget(const gfx::PointF& point) {
     position_in_widget_ = point;
   }
diff --git a/third_party/blink/public/common/input/web_input_event.h b/third_party/blink/public/common/input/web_input_event.h
index c137231c75f1..5d30b5eaab6a 100644
--- a/third_party/blink/public/common/input/web_input_event.h
+++ b/third_party/blink/public/common/input/web_input_event.h
@@ -42,7 +42,7 @@ namespace blink {
 
 // WebInputEvent --------------------------------------------------------------
 
-class WebInputEvent {
+class BLINK_COMMON_EXPORT WebInputEvent {
  public:
   // When we use an input method (or an input method editor), we receive
   // two events for a keypress. The former event is a keydown, which
@@ -426,61 +426,30 @@ class WebInputEvent {
   base::TimeTicks TimeStamp() const { return time_stamp_; }
   void SetTimeStamp(base::TimeTicks time_stamp) { time_stamp_ = time_stamp; }
 
-  unsigned size() const { return size_; }
-
   void SetTargetFrameMovedRecently() {
     modifiers_ |= kTargetFrameMovedRecently;
   }
 
+  virtual ~WebInputEvent() = default;
+
+  virtual std::unique_ptr<WebInputEvent> Clone() const = 0;
+
  protected:
   // The root frame scale.
-  float frame_scale_;
+  float frame_scale_ = 1;
 
   // The root frame translation (applied post scale).
   gfx::Vector2dF frame_translate_;
 
-  WebInputEvent(unsigned size,
-                Type type,
-                int modifiers,
-                base::TimeTicks time_stamp) {
-    // TODO(dtapuska): Remove this memset when we remove the chrome IPC of this
-    // struct.
-    memset(this, 0, size);
-    time_stamp_ = time_stamp;
-    size_ = size;
-    type_ = type;
-    modifiers_ = modifiers;
-#if DCHECK_IS_ON()
-    // If dcheck is on force failures if frame scale is not initialized
-    // correctly by causing DIV0.
-    frame_scale_ = 0;
-#else
-    frame_scale_ = 1;
-#endif
-  }
+  WebInputEvent(Type type, int modifiers, base::TimeTicks time_stamp)
+      : time_stamp_(time_stamp), type_(type), modifiers_(modifiers) {}
 
-  explicit WebInputEvent(unsigned size_param) {
-    // TODO(dtapuska): Remove this memset when we remove the chrome IPC of this
-    // struct.
-    memset(this, 0, size_param);
-    time_stamp_ = base::TimeTicks();
-    size_ = size_param;
-    type_ = kUndefined;
-#if DCHECK_IS_ON()
-    // If dcheck is on force failures if frame scale is not initialized
-    // correctly by causing DIV0.
-    frame_scale_ = 0;
-#else
-    frame_scale_ = 1;
-#endif
-  }
+  WebInputEvent() { time_stamp_ = base::TimeTicks(); }
 
   // Event time since platform start with microsecond resolution.
   base::TimeTicks time_stamp_;
-  // The size of this structure, for serialization.
-  unsigned size_;
-  Type type_;
-  int modifiers_;
+  Type type_ = kUndefined;
+  int modifiers_ = kNoModifiers;
 };
 
 }  // namespace blink
diff --git a/third_party/blink/public/common/input/web_keyboard_event.h b/third_party/blink/public/common/input/web_keyboard_event.h
index 18cfb20dbe32..5f38e9ec8fa0 100644
--- a/third_party/blink/public/common/input/web_keyboard_event.h
+++ b/third_party/blink/public/common/input/web_keyboard_event.h
@@ -12,7 +12,7 @@ namespace blink {
 
 // WebKeyboardEvent -----------------------------------------------------------
 
-class WebKeyboardEvent : public WebInputEvent {
+class BLINK_COMMON_EXPORT WebKeyboardEvent : public WebInputEvent {
  public:
   // Caps on string lengths so we can make them static arrays and keep
   // them PODs.
@@ -26,32 +26,32 @@ class WebKeyboardEvent : public WebInputEvent {
   // what is returned by the Windows API. For example, it should
   // store VK_SHIFT instead of VK_RSHIFT. The location information
   // should be stored in |modifiers|.
-  int windows_key_code;
+  int windows_key_code = 0;
 
   // The actual key code genenerated by the platform. The DOM spec runs
   // on Windows-equivalent codes (thus |windows_key_code| above) but it
   // doesn't hurt to have this one around.
-  int native_key_code;
+  int native_key_code = 0;
 
   // The DOM code enum of the key pressed as passed by the embedder. DOM code
   // enums are defined in ui/events/keycodes/dom/keycode_converter_data.inc.
-  int dom_code;
+  int dom_code = 0;
 
   // The DOM key enum of the key pressed as passed by the embedder. DOM
   // key enums are defined in ui/events/keycodes/dom/dom_key_data.inc.
-  int dom_key;
+  int dom_key = 0;
 
   // This identifies whether this event was tagged by the system as being a
   // "system key" event (see
   // https://docs.microsoft.com/en-us/windows/desktop/inputdev/wm-syskeydown for
   // details). Other platforms don't have this concept, but it's just
   // easier to leave it always false than ifdef.
-  bool is_system_key;
+  bool is_system_key = false;
 
   // Whether the event forms part of a browser-handled keyboard shortcut.
   // This can be used to conditionally suppress Char events after a
   // shortcut-triggering RawKeyDown goes unhandled.
-  bool is_browser_shortcut;
+  bool is_browser_shortcut = false;
 
   // |text| is the text generated by this keystroke.  |unmodified_text| is
   // |text|, but unmodified by an concurrently-held modifiers (except
@@ -59,13 +59,15 @@ class WebKeyboardEvent : public WebInputEvent {
   // Windows guarantee one character per event.  The Mac does not, but in
   // reality that's all it ever gives.  We're generous, and cap it a bit
   // longer.
-  base::char16 text[kTextLengthCap];
-  base::char16 unmodified_text[kTextLengthCap];
+  base::char16 text[kTextLengthCap] = {};
+  base::char16 unmodified_text[kTextLengthCap] = {};
 
   WebKeyboardEvent(Type type, int modifiers, base::TimeTicks time_stamp)
-      : WebInputEvent(sizeof(WebKeyboardEvent), type, modifiers, time_stamp) {}
+      : WebInputEvent(type, modifiers, time_stamp) {}
 
-  WebKeyboardEvent() : WebInputEvent(sizeof(WebKeyboardEvent)) {}
+  WebKeyboardEvent() = default;
+
+  std::unique_ptr<WebInputEvent> Clone() const override;
 
   // Please refer to bug http://b/issue?id=961192, which talks about Webkit
   // keyboard event handling changes. It also mentions the list of keys
diff --git a/third_party/blink/public/common/input/web_mouse_event.h b/third_party/blink/public/common/input/web_mouse_event.h
index 25da4f16f58a..957e83c238b9 100644
--- a/third_party/blink/public/common/input/web_mouse_event.h
+++ b/third_party/blink/public/common/input/web_mouse_event.h
@@ -20,10 +20,10 @@ class BLINK_COMMON_EXPORT WebMouseEvent : public WebInputEvent,
  public:
   static constexpr PointerId kMousePointerId = std::numeric_limits<int>::max();
 
-  int click_count;
+  int click_count = {};
 
   // Only used for contextmenu events.
-  WebMenuSourceType menu_source_type;
+  WebMenuSourceType menu_source_type = kMenuSourceNone;
 
   WebMouseEvent(Type type_param,
                 gfx::PointF position,
@@ -34,10 +34,7 @@ class BLINK_COMMON_EXPORT WebMouseEvent : public WebInputEvent,
                 base::TimeTicks time_stamp_param,
                 WebMenuSourceType menu_source_type_param = kMenuSourceNone,
                 PointerId id_param = kMousePointerId)
-      : WebInputEvent(sizeof(WebMouseEvent),
-                      type_param,
-                      modifiers_param,
-                      time_stamp_param),
+      : WebInputEvent(type_param, modifiers_param, time_stamp_param),
         WebPointerProperties(id_param,
                              PointerType::kMouse,
                              button_param,
@@ -53,13 +50,10 @@ class BLINK_COMMON_EXPORT WebMouseEvent : public WebInputEvent,
                 int modifiers_param,
                 base::TimeTicks time_stamp_param,
                 PointerId id_param = kMousePointerId)
-      : WebMouseEvent(sizeof(WebMouseEvent),
-                      type_param,
-                      modifiers_param,
-                      time_stamp_param,
-                      id_param) {}
+      : WebInputEvent(type_param, modifiers_param, time_stamp_param),
+        WebPointerProperties(id_param) {}
 
-  WebMouseEvent() : WebMouseEvent(sizeof(WebMouseEvent), kMousePointerId) {}
+  WebMouseEvent() : WebMouseEvent(kMousePointerId) {}
 
   bool FromTouch() const {
     return (GetModifiers() & kIsCompatibilityEventForTouch) != 0;
@@ -73,6 +67,8 @@ class BLINK_COMMON_EXPORT WebMouseEvent : public WebInputEvent,
                 base::TimeTicks time_stamp_param,
                 PointerId id_param = kMousePointerId);
 
+  std::unique_ptr<WebInputEvent> Clone() const override;
+
   gfx::PointF PositionInRootFrame() const;
 
   // Sets any scaled values to be their computed values and sets |frame_scale_|
@@ -80,16 +76,7 @@ class BLINK_COMMON_EXPORT WebMouseEvent : public WebInputEvent,
   WebMouseEvent FlattenTransform() const;
 
  protected:
-  WebMouseEvent(unsigned size_param, PointerId id_param)
-      : WebInputEvent(size_param), WebPointerProperties(id_param) {}
-
-  WebMouseEvent(unsigned size_param,
-                Type type,
-                int modifiers,
-                base::TimeTicks time_stamp,
-                PointerId id_param)
-      : WebInputEvent(size_param, type, modifiers, time_stamp),
-        WebPointerProperties(id_param) {}
+  WebMouseEvent(PointerId id_param) : WebPointerProperties(id_param) {}
 
   void FlattenTransformSelf();
 
diff --git a/third_party/blink/public/common/input/web_mouse_wheel_event.h b/third_party/blink/public/common/input/web_mouse_wheel_event.h
index 605740b8c01d..79697fe69e08 100644
--- a/third_party/blink/public/common/input/web_mouse_wheel_event.h
+++ b/third_party/blink/public/common/input/web_mouse_wheel_event.h
@@ -52,25 +52,25 @@ class BLINK_COMMON_EXPORT WebMouseWheelEvent : public WebMouseEvent {
     kScrollVertical
   };
 
-  float delta_x;
-  float delta_y;
-  float wheel_ticks_x;
-  float wheel_ticks_y;
+  float delta_x = 0.0f;
+  float delta_y = 0.0f;
+  float wheel_ticks_x = 0.0f;
+  float wheel_ticks_y = 0.0f;
 
-  float acceleration_ratio_x;
-  float acceleration_ratio_y;
+  float acceleration_ratio_x = 1.0f;
+  float acceleration_ratio_y = 1.0f;
 
-  Phase phase;
-  Phase momentum_phase;
+  Phase phase = kPhaseNone;
+  Phase momentum_phase = kPhaseNone;
 
-  RailsMode rails_mode;
+  RailsMode rails_mode = kRailsModeFree;
 
   // Whether the event is blocking, non-blocking, all event
   // listeners were passive or was forced to be non-blocking.
-  DispatchType dispatch_type;
+  DispatchType dispatch_type = kBlocking;
 
   // The expected result of this wheel event (if not canceled).
-  EventAction event_action;
+  EventAction event_action = EventAction::kPageZoom;
 
   // True when phase information is added in mouse_wheel_phase_handler based
   // on its timer.
@@ -80,39 +80,13 @@ class BLINK_COMMON_EXPORT WebMouseWheelEvent : public WebMouseEvent {
   // kScrollByPrecisePixel, kScrollByPixel, and kScrollByPage, as they are
   // the only values expected after converting an OS event to a
   // WebMouseWheelEvent.
-  ui::input_types::ScrollGranularity delta_units;
+  ui::input_types::ScrollGranularity delta_units =
+      ui::input_types::ScrollGranularity::kScrollByPixel;
 
   WebMouseWheelEvent(Type type, int modifiers, base::TimeTicks time_stamp)
-      : WebMouseEvent(sizeof(WebMouseWheelEvent),
-                      type,
-                      modifiers,
-                      time_stamp,
-                      kMousePointerId),
-        delta_x(0.0f),
-        delta_y(0.0f),
-        wheel_ticks_x(0.0f),
-        wheel_ticks_y(0.0f),
-        acceleration_ratio_x(1.0f),
-        acceleration_ratio_y(1.0f),
-        phase(kPhaseNone),
-        momentum_phase(kPhaseNone),
-        rails_mode(kRailsModeFree),
-        dispatch_type(kBlocking),
-        delta_units(ui::input_types::ScrollGranularity::kScrollByPixel) {}
-
-  WebMouseWheelEvent()
-      : WebMouseEvent(sizeof(WebMouseWheelEvent), kMousePointerId),
-        delta_x(0.0f),
-        delta_y(0.0f),
-        wheel_ticks_x(0.0f),
-        wheel_ticks_y(0.0f),
-        acceleration_ratio_x(1.0f),
-        acceleration_ratio_y(1.0f),
-        phase(kPhaseNone),
-        momentum_phase(kPhaseNone),
-        rails_mode(kRailsModeFree),
-        dispatch_type(kBlocking),
-        delta_units(ui::input_types::ScrollGranularity::kScrollByPixel) {}
+      : WebMouseEvent(type, modifiers, time_stamp, kMousePointerId) {}
+
+  WebMouseWheelEvent() : WebMouseEvent(kMousePointerId) {}
 
   float DeltaXInRootFrame() const;
   float DeltaYInRootFrame() const;
@@ -122,6 +96,8 @@ class BLINK_COMMON_EXPORT WebMouseWheelEvent : public WebMouseEvent {
   WebMouseWheelEvent FlattenTransform() const;
 
   bool IsCancelable() const { return dispatch_type == kBlocking; }
+
+  std::unique_ptr<WebInputEvent> Clone() const override;
 };
 
 }  // namespace blink
diff --git a/third_party/blink/public/common/input/web_pointer_event.h b/third_party/blink/public/common/input/web_pointer_event.h
index cdf6b9984dcb..efb5847eb8ec 100644
--- a/third_party/blink/public/common/input/web_pointer_event.h
+++ b/third_party/blink/public/common/input/web_pointer_event.h
@@ -21,14 +21,12 @@ namespace blink {
 class BLINK_COMMON_EXPORT WebPointerEvent : public WebInputEvent,
                                             public WebPointerProperties {
  public:
-  WebPointerEvent()
-      : WebInputEvent(sizeof(WebPointerEvent)), WebPointerProperties(0) {}
+  WebPointerEvent() : WebPointerProperties(0) {}
   WebPointerEvent(WebInputEvent::Type type_param,
                   WebPointerProperties web_pointer_properties_param,
                   float width_param,
                   float height_param)
-      : WebInputEvent(sizeof(WebPointerEvent)),
-        WebPointerProperties(web_pointer_properties_param),
+      : WebPointerProperties(web_pointer_properties_param),
         width(width_param),
         height(height_param) {
     SetType(type_param);
@@ -36,44 +34,46 @@ class BLINK_COMMON_EXPORT WebPointerEvent : public WebInputEvent,
   WebPointerEvent(const WebTouchEvent&, const WebTouchPoint&);
   WebPointerEvent(WebInputEvent::Type, const WebMouseEvent&);
 
+  std::unique_ptr<WebInputEvent> Clone() const override;
+
   static WebPointerEvent CreatePointerCausesUaActionEvent(
       WebPointerProperties::PointerType,
       base::TimeTicks time_stamp);
 
   // ------------ Touch Point Specific ------------
 
-  float rotation_angle;
+  float rotation_angle = 0.0f;
 
   // ------------ Touch Event Specific ------------
 
   // A unique identifier for the touch event. Valid ids start at one and
   // increase monotonically. Zero means an unknown id.
-  uint32_t unique_touch_event_id;
+  uint32_t unique_touch_event_id = 0;
 
   // Whether the event is blocking, non-blocking, all event
   // listeners were passive or was forced to be non-blocking.
-  DispatchType dispatch_type;
+  DispatchType dispatch_type = kBlocking;
 
   // For a single touch, this is true after the touch-point has moved beyond
   // the platform slop region. For a multitouch, this is true after any
   // touch-point has moved (by whatever amount).
-  bool moved_beyond_slop_region;
+  bool moved_beyond_slop_region = false;
 
   // Whether this touch event is a touchstart or a first touchmove event per
   // scroll.
-  bool touch_start_or_first_touch_move;
+  bool touch_start_or_first_touch_move = false;
 
   // ------------ Common fields across pointer types ------------
 
   // True if this pointer was hovering and false otherwise. False value entails
   // the event was processed as part of gesture detection and it may cause
   // scrolling.
-  bool hovering;
+  bool hovering = false;
 
   // TODO(crbug.com/736014): We need a clarified definition of the scale and
   // the coordinate space on these attributes.
-  float width;
-  float height;
+  float width = 0.0f;
+  float height = 0.0f;
 
   bool IsCancelable() const { return dispatch_type == kBlocking; }
   bool HasWidth() const { return !std::isnan(width); }
diff --git a/third_party/blink/public/common/input/web_pointer_properties.h b/third_party/blink/public/common/input/web_pointer_properties.h
index d122090fde30..c642fab9da4c 100644
--- a/third_party/blink/public/common/input/web_pointer_properties.h
+++ b/third_party/blink/public/common/input/web_pointer_properties.h
@@ -60,16 +60,10 @@ class WebPointerProperties {
       int movement_x = 0,
       int movement_y = 0)
       : id(id_param),
-        force(std::numeric_limits<float>::quiet_NaN()),
-        tilt_x(0),
-        tilt_y(0),
-        tangential_pressure(0.0f),
-        twist(0),
         button(button_param),
         pointer_type(pointer_type_param),
         movement_x(movement_x),
         movement_y(movement_y),
-        is_raw_movement_event(false),
         position_in_widget_(position_in_widget),
         position_in_screen_(position_in_screen) {}
 
@@ -96,23 +90,23 @@ class WebPointerProperties {
 
   // The valid range is [0,1], with NaN meaning pressure is not supported by
   // the input device.
-  float force;
+  float force = std::numeric_limits<float>::quiet_NaN();
 
   // Tilt of a pen stylus from surface normal as plane angles in degrees,
   // Values lie in [-90,90]. A positive tiltX is to the right and a positive
   // tiltY is towards the user.
-  int tilt_x;
-  int tilt_y;
+  int tilt_x = 0;
+  int tilt_y = 0;
 
   // The normalized tangential pressure (or barrel pressure), typically set by
   // an additional control of the stylus, which has a range of [-1,1], where 0
   // is the neutral position of the control. Always 0 if the device does not
   // support it.
-  float tangential_pressure;
+  float tangential_pressure = 0.0f;
 
   // The clockwise rotation of a pen stylus around its own major axis, in
   // degrees in the range [0,359]. Always 0 if the device does not support it.
-  int twist;
+  int twist = 0;
 
   // - For pointerup/down events, the button of pointing device that triggered
   // the event.
@@ -128,7 +122,7 @@ class WebPointerProperties {
 
   // True if this event has raw movement value from OS.
   // TODO(crbug.com/982379): Figure out how to avoid using this boolean.
-  bool is_raw_movement_event;
+  bool is_raw_movement_event = false;
 
  protected:
   // Widget coordinate, which is relative to the bound of current RenderWidget
diff --git a/third_party/blink/public/common/input/web_touch_event.h b/third_party/blink/public/common/input/web_touch_event.h
index 795976c6a8f8..9a59b3f63120 100644
--- a/third_party/blink/public/common/input/web_touch_event.h
+++ b/third_party/blink/public/common/input/web_touch_event.h
@@ -19,37 +19,37 @@ class BLINK_COMMON_EXPORT WebTouchEvent : public WebInputEvent {
   // Ash/Aura.
   enum { kTouchesLengthCap = 16 };
 
-  unsigned touches_length;
+  unsigned touches_length = 0;
   // List of all touches, regardless of state.
-  WebTouchPoint touches[kTouchesLengthCap];
+  WebTouchPoint touches[kTouchesLengthCap] = {};
 
   // Whether the event is blocking, non-blocking, all event
   // listeners were passive or was forced to be non-blocking.
-  DispatchType dispatch_type;
+  DispatchType dispatch_type = kBlocking;
 
   // For a single touch, this is true after the touch-point has moved beyond
   // the platform slop region. For a multitouch, this is true after any
   // touch-point has moved (by whatever amount).
-  bool moved_beyond_slop_region;
+  bool moved_beyond_slop_region = false;
 
   // True for events from devices like some pens that support hovering
   // over digitizer and the events are sent while the device was hovering.
-  bool hovering;
+  bool hovering = false;
 
   // Whether this touch event is a touchstart or a first touchmove event per
   // scroll.
-  bool touch_start_or_first_touch_move;
+  bool touch_start_or_first_touch_move = false;
 
   // A unique identifier for the touch event. Valid ids start at one and
   // increase monotonically. Zero means an unknown id.
-  uint32_t unique_touch_event_id;
+  uint32_t unique_touch_event_id = 0;
 
-  WebTouchEvent()
-      : WebInputEvent(sizeof(WebTouchEvent)), dispatch_type(kBlocking) {}
+  WebTouchEvent() = default;
 
   WebTouchEvent(Type type, int modifiers, base::TimeTicks time_stamp)
-      : WebInputEvent(sizeof(WebTouchEvent), type, modifiers, time_stamp),
-        dispatch_type(kBlocking) {}
+      : WebInputEvent(type, modifiers, time_stamp) {}
+
+  std::unique_ptr<WebInputEvent> Clone() const override;
 
   // Sets any scaled values to be their computed values and sets |frame_scale_|
   // back to 1 and |frame_translate_| X and Y coordinates back to 0.
diff --git a/third_party/blink/public/common/input/web_touch_point.h b/third_party/blink/public/common/input/web_touch_point.h
index de8971f66487..939142edb2bc 100644
--- a/third_party/blink/public/common/input/web_touch_point.h
+++ b/third_party/blink/public/common/input/web_touch_point.h
@@ -38,16 +38,12 @@ namespace blink {
 
 // TODO(mustaq): Unify WebTouchPoint & WebMouseEvent into WebPointerEvent.
 // crbug.com/508283
-class WebTouchPoint : public WebPointerProperties {
+class BLINK_COMMON_EXPORT WebTouchPoint : public WebPointerProperties {
  public:
   WebTouchPoint() : WebTouchPoint(WebPointerProperties(0)) {}
 
   WebTouchPoint(WebPointerProperties web_pointer_properties)
-      : WebPointerProperties(web_pointer_properties),
-        state(kStateUndefined),
-        radius_x(0),
-        radius_y(0),
-        rotation_angle(0) {}
+      : WebPointerProperties(web_pointer_properties) {}
 
   enum State {
     kStateUndefined,
@@ -59,11 +55,11 @@ class WebTouchPoint : public WebPointerProperties {
     kStateMax = kStateCancelled
   };
 
-  State state;
+  State state = kStateUndefined;
 
-  float radius_x;
-  float radius_y;
-  float rotation_angle;
+  float radius_x = 0.0f;
+  float radius_y = 0.0f;
+  float rotation_angle = 0.0f;
 };
 
 }  // namespace blink
diff --git a/third_party/blink/public/platform/web_coalesced_input_event.h b/third_party/blink/public/platform/web_coalesced_input_event.h
index bcf0359482c7..3095d0bb524d 100644
--- a/third_party/blink/public/platform/web_coalesced_input_event.h
+++ b/third_party/blink/public/platform/web_coalesced_input_event.h
@@ -42,12 +42,7 @@ class BLINK_PLATFORM_EXPORT WebCoalescedInputEvent {
   WebVector<const WebInputEvent*> GetPredictedEventsPointers() const;
 
  private:
-  struct BLINK_PLATFORM_EXPORT WebInputEventDeleter {
-    void operator()(blink::WebInputEvent*) const;
-  };
-
-  using WebScopedInputEvent =
-      std::unique_ptr<WebInputEvent, WebInputEventDeleter>;
+  using WebScopedInputEvent = std::unique_ptr<WebInputEvent>;
 
   WebScopedInputEvent MakeWebScopedInputEvent(const blink::WebInputEvent&);
 
diff --git a/third_party/blink/renderer/core/events/web_input_event_conversion.cc b/third_party/blink/renderer/core/events/web_input_event_conversion.cc
index 716617985147..fcf3fc6b4aff 100644
--- a/third_party/blink/renderer/core/events/web_input_event_conversion.cc
+++ b/third_party/blink/renderer/core/events/web_input_event_conversion.cc
@@ -120,8 +120,8 @@ unsigned ToWebInputEventModifierFrom(WebMouseEvent::Button button) {
 WebPointerEvent TransformWebPointerEvent(float frame_scale,
                                          gfx::Vector2dF frame_translate,
                                          const WebPointerEvent& event) {
-  // frameScale is default initialized in debug builds to be 0.
-  DCHECK_EQ(0, event.FrameScale());
+  // frameScale is default initialized to 1.
+  DCHECK_EQ(1, event.FrameScale());
   DCHECK_EQ(0, event.FrameTranslate().x());
   DCHECK_EQ(0, event.FrameTranslate().y());
   WebPointerEvent result = event;
diff --git a/third_party/blink/renderer/platform/exported/web_coalesced_input_event.cc b/third_party/blink/renderer/platform/exported/web_coalesced_input_event.cc
index ac42cd792eb1..21edc5fe3070 100644
--- a/third_party/blink/renderer/platform/exported/web_coalesced_input_event.cc
+++ b/third_party/blink/renderer/platform/exported/web_coalesced_input_event.cc
@@ -12,46 +12,6 @@
 
 namespace blink {
 
-namespace {
-
-struct WebInputEventDelete {
-  template <class EventType>
-  bool Execute(WebInputEvent* event) const {
-    if (!event)
-      return false;
-    DCHECK_EQ(sizeof(EventType), event->size());
-    delete static_cast<EventType*>(event);
-    return true;
-  }
-};
-
-template <typename Operator, typename ArgIn>
-bool Apply(Operator op, WebInputEvent::Type type, const ArgIn& arg_in) {
-  if (WebInputEvent::IsMouseEventType(type))
-    return op.template Execute<WebMouseEvent>(arg_in);
-  if (type == WebInputEvent::kMouseWheel)
-    return op.template Execute<WebMouseWheelEvent>(arg_in);
-  if (WebInputEvent::IsKeyboardEventType(type))
-    return op.template Execute<WebKeyboardEvent>(arg_in);
-  if (WebInputEvent::IsTouchEventType(type))
-    return op.template Execute<WebTouchEvent>(arg_in);
-  if (WebInputEvent::IsGestureEventType(type))
-    return op.template Execute<WebGestureEvent>(arg_in);
-  if (WebInputEvent::IsPointerEventType(type))
-    return op.template Execute<WebPointerEvent>(arg_in);
-
-  NOTREACHED() << "Unknown webkit event type " << type;
-  return false;
-}
-}
-
-void WebCoalescedInputEvent::WebInputEventDeleter::operator()(
-    WebInputEvent* event) const {
-  if (!event)
-    return;
-  Apply(WebInputEventDelete(), event->GetType(), event);
-}
-
 WebInputEvent* WebCoalescedInputEvent::EventPointer() {
   return event_.get();
 }
diff --git a/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl_unittest.cc b/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl_unittest.cc
index 63d7ca8fb6e6..c44eecf2c2bd 100644
--- a/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl_unittest.cc
+++ b/third_party/blink/renderer/platform/scheduler/main_thread/main_thread_scheduler_impl_unittest.cc
@@ -58,10 +58,13 @@ class FakeInputEvent : public blink::WebInputEvent {
  public:
   explicit FakeInputEvent(blink::WebInputEvent::Type event_type,
                           int modifiers = WebInputEvent::kNoModifiers)
-      : WebInputEvent(sizeof(FakeInputEvent),
-                      event_type,
+      : WebInputEvent(event_type,
                       modifiers,
                       WebInputEvent::GetStaticTimeStampForTests()) {}
+
+  std::unique_ptr<WebInputEvent> Clone() const override {
+    return std::make_unique<FakeInputEvent>(*this);
+  }
 };
 
 class FakeTouchEvent : public blink::WebTouchEvent {
diff --git a/ui/events/blink/compositor_thread_event_queue.cc b/ui/events/blink/compositor_thread_event_queue.cc
index f9c2b4609121..8d4e06475878 100644
--- a/ui/events/blink/compositor_thread_event_queue.cc
+++ b/ui/events/blink/compositor_thread_event_queue.cc
@@ -76,12 +76,12 @@ void CompositorThreadEventQueue::Queue(
 
   std::unique_ptr<EventWithCallback> scroll_event =
       std::make_unique<EventWithCallback>(
-          WebInputEventTraits::Clone(coalesced_events.first), oldest_latency,
+          coalesced_events.first.Clone(), oldest_latency,
           oldest_creation_timestamp, timestamp_now, nullptr);
 
   std::unique_ptr<EventWithCallback> pinch_event =
       std::make_unique<EventWithCallback>(
-          WebInputEventTraits::Clone(coalesced_events.second), oldest_latency,
+          coalesced_events.second.Clone(), oldest_latency,
           oldest_creation_timestamp, timestamp_now,
           std::move(combined_original_events));
 
diff --git a/ui/events/blink/event_with_callback.cc b/ui/events/blink/event_with_callback.cc
index cbed00131204..c3c685dbae2c 100644
--- a/ui/events/blink/event_with_callback.cc
+++ b/ui/events/blink/event_with_callback.cc
@@ -19,7 +19,7 @@ EventWithCallback::EventWithCallback(
     const LatencyInfo& latency,
     base::TimeTicks timestamp_now,
     InputHandlerProxy::EventDispositionCallback callback)
-    : event_(WebInputEventTraits::Clone(*event)),
+    : event_(event->Clone()),
       latency_(latency),
       creation_timestamp_(timestamp_now),
       last_coalesced_timestamp_(timestamp_now) {
diff --git a/ui/events/blink/input_handler_proxy_unittest.cc b/ui/events/blink/input_handler_proxy_unittest.cc
index cf89aaa43cf7..9b2b867f2944 100644
--- a/ui/events/blink/input_handler_proxy_unittest.cc
+++ b/ui/events/blink/input_handler_proxy_unittest.cc
@@ -94,7 +94,7 @@ WebScopedInputEvent CreateGestureScrollPinch(WebInputEvent::Type type,
     gesture.data.pinch_update.scale = delta_y_or_scale;
     gesture.SetPositionInWidget(gfx::PointF(x, y));
   }
-  return WebInputEventTraits::Clone(gesture);
+  return gesture.Clone();
 }
 
 class MockInputHandler : public cc::InputHandler {
@@ -2640,14 +2640,14 @@ class InputHandlerProxyMomentumScrollJankTest : public testing::Test {
     WebGestureEvent gesture(WebInputEvent::kGestureScrollBegin,
                             WebInputEvent::kNoModifiers, tick_clock_.NowTicks(),
                             blink::WebGestureDevice::kTouchscreen);
-    HandleGesture(WebInputEventTraits::Clone(gesture));
+    HandleGesture(gesture.Clone());
   }
 
   void HandleScrollEnd() {
     WebGestureEvent gesture(WebInputEvent::kGestureScrollEnd,
                             WebInputEvent::kNoModifiers, tick_clock_.NowTicks(),
                             blink::WebGestureDevice::kTouchscreen);
-    HandleGesture(WebInputEventTraits::Clone(gesture));
+    HandleGesture(gesture.Clone());
   }
 
   void HandleScrollUpdate(bool is_momentum) {
@@ -2659,7 +2659,7 @@ class InputHandlerProxyMomentumScrollJankTest : public testing::Test {
       gesture.data.scroll_update.inertial_phase =
           blink::WebGestureEvent::InertialPhaseState::kMomentum;
     }
-    HandleGesture(WebInputEventTraits::Clone(gesture));
+    HandleGesture(gesture.Clone());
   }
 
   void AdvanceClock(uint32_t milliseconds) {
diff --git a/ui/events/blink/scroll_predictor_unittest.cc b/ui/events/blink/scroll_predictor_unittest.cc
index cbf1b8830690..e8409d23eb4a 100644
--- a/ui/events/blink/scroll_predictor_unittest.cc
+++ b/ui/events/blink/scroll_predictor_unittest.cc
@@ -58,10 +58,10 @@ class ScrollPredictorTest : public testing::Test {
     gesture.data.scroll_update.delta_y = delta_y;
     gesture.data.scroll_update.inertial_phase = phase;
 
-    original_events_.emplace_back(WebInputEventTraits::Clone(gesture),
-                                  LatencyInfo(), base::NullCallback());
+    original_events_.emplace_back(gesture.Clone(), LatencyInfo(),
+                                  base::NullCallback());
 
-    return WebInputEventTraits::Clone(gesture);
+    return gesture.Clone();
   }
 
   void CoalesceWith(const WebScopedInputEvent& new_event,
@@ -90,7 +90,7 @@ class ScrollPredictorTest : public testing::Test {
         WebInputEvent::GetStaticTimeStampForTests() +
             base::TimeDelta::FromMillisecondsD(time_delta_in_milliseconds));
 
-    event = WebInputEventTraits::Clone(event_with_callback->event());
+    event = event_with_callback->event().Clone();
   }
 
   std::unique_ptr<ui::InputPredictor::InputData> PredictionAvailable(
@@ -203,7 +203,7 @@ TEST_F(ScrollPredictorTest, ScrollResamplingStates) {
                               WebInputEvent::kNoModifiers,
                               WebInputEvent::GetStaticTimeStampForTests(),
                               blink::WebGestureDevice::kTouchscreen);
-  WebScopedInputEvent event = WebInputEventTraits::Clone(gesture_end);
+  WebScopedInputEvent event = gesture_end.Clone();
   HandleResampleScrollEvents(event);
   EXPECT_FALSE(GetResamplingState());
 }
diff --git a/ui/events/blink/web_input_event_traits.cc b/ui/events/blink/web_input_event_traits.cc
index 9734e1d0cd9d..19bd615be35b 100644
--- a/ui/events/blink/web_input_event_traits.cc
+++ b/ui/events/blink/web_input_event_traits.cc
@@ -105,17 +105,6 @@ void ApppendEventDetails(const WebPointerEvent& event, std::string* result) {
       event.rotation_angle, event.tilt_x, event.tilt_y);
 }
 
-struct WebInputEventDelete {
-  template <class EventType>
-  bool Execute(WebInputEvent* event, void*) const {
-    if (!event)
-      return false;
-    DCHECK_EQ(sizeof(EventType), event->size());
-    delete static_cast<EventType*>(event);
-    return true;
-  }
-};
-
 struct WebInputEventToString {
   template <class EventType>
   bool Execute(const WebInputEvent& event, std::string* result) const {
@@ -129,17 +118,6 @@ struct WebInputEventToString {
   }
 };
 
-struct WebInputEventClone {
-  template <class EventType>
-  bool Execute(const WebInputEvent& event,
-               WebScopedInputEvent* scoped_event) const {
-    DCHECK_EQ(sizeof(EventType), event.size());
-    *scoped_event = WebScopedInputEvent(
-        new EventType(static_cast<const EventType&>(event)));
-    return true;
-  }
-};
-
 template <typename Operator, typename ArgIn, typename ArgOut>
 bool Apply(Operator op,
            WebInputEvent::Type type,
@@ -164,25 +142,12 @@ bool Apply(Operator op,
 
 }  // namespace
 
-void WebInputEventDeleter::operator()(WebInputEvent* event) const {
-  if (!event)
-    return;
-  void* temp = nullptr;
-  Apply(WebInputEventDelete(), event->GetType(), event, temp);
-}
-
 std::string WebInputEventTraits::ToString(const WebInputEvent& event) {
   std::string result;
   Apply(WebInputEventToString(), event.GetType(), event, &result);
   return result;
 }
 
-WebScopedInputEvent WebInputEventTraits::Clone(const WebInputEvent& event) {
-  WebScopedInputEvent scoped_event;
-  Apply(WebInputEventClone(), event.GetType(), event, &scoped_event);
-  return scoped_event;
-}
-
 bool WebInputEventTraits::ShouldBlockEventStream(const WebInputEvent& event) {
   switch (event.GetType()) {
     case WebInputEvent::kContextMenu:
diff --git a/ui/events/blink/web_input_event_traits.h b/ui/events/blink/web_input_event_traits.h
index 19f9db8bd44c..10f60ba4eb0b 100644
--- a/ui/events/blink/web_input_event_traits.h
+++ b/ui/events/blink/web_input_event_traits.h
@@ -14,18 +14,12 @@ class WebGestureEvent;
 
 namespace ui {
 
-struct WebInputEventDeleter {
-  void operator()(blink::WebInputEvent*) const;
-};
-
-using WebScopedInputEvent =
-    std::unique_ptr<blink::WebInputEvent, WebInputEventDeleter>;
+using WebScopedInputEvent = std::unique_ptr<blink::WebInputEvent>;
 
 // Utility class for performing operations on and with WebInputEvents.
 class WebInputEventTraits {
  public:
   static std::string ToString(const blink::WebInputEvent& event);
-  static WebScopedInputEvent Clone(const blink::WebInputEvent& event);
   static bool ShouldBlockEventStream(const blink::WebInputEvent& event);
 
   // Return uniqueTouchEventId for WebTouchEvent, otherwise return 0.
-- 
2.24.1