Keep track of coalesced events in main thread event queue

content/common/input/event_with_latency_info.cc

 // Copyright 2016 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 "content/common/input/event_with_latency_info.h"
 
 using blink::WebInputEvent;
 
 namespace content {
 
 ScopedWebInputEventWithLatencyInfo::ScopedWebInputEventWithLatencyInfo(
     blink::WebScopedInputEvent event,
     const ui::LatencyInfo& latency_info)
-    : event_(std::move(event)), latency_(latency_info) {}
+    : event_(new blink::WebCoalescedInputEvent(std::move(event))),
+      latency_(latency_info) {}
 
 ScopedWebInputEventWithLatencyInfo::~ScopedWebInputEventWithLatencyInfo() {}
 
 bool ScopedWebInputEventWithLatencyInfo::CanCoalesceWith(
     const ScopedWebInputEventWithLatencyInfo& other) const {
   return ui::CanCoalesce(other.event(), event());
 }
 
 void ScopedWebInputEventWithLatencyInfo::CoalesceWith(
     const ScopedWebInputEventWithLatencyInfo& other) {
   // |other| should be a newer event than |this|.
   if (other.latency_.trace_id() >= 0 && latency_.trace_id() >= 0)
     DCHECK_GT(other.latency_.trace_id(), latency_.trace_id());
 
   // New events get coalesced into older events, and the newer timestamp
   // should always be preserved.
   const double time_stamp_seconds = other.event().timeStampSeconds();
-  ui::Coalesce(other.event(), event_.get());
-  event_->setTimeStampSeconds(time_stamp_seconds);
+  ui::Coalesce(other.event(), event_->eventPointer());
+  event_->eventPointer()->setTimeStampSeconds(time_stamp_seconds);
+  event_->addCoalescedEvent(other.event());
 
   // When coalescing two input events, we keep the oldest LatencyInfo
   // since it will represent the longest latency.
   other.latency_ = latency_;
   other.latency_.set_coalesced();
 }
 
 const blink::WebInputEvent& ScopedWebInputEventWithLatencyInfo::event() const {
+  return event_->event();
+}
+
+blink::WebInputEvent& ScopedWebInputEventWithLatencyInfo::event() {
+  return *event_->eventPointer();
+}
+
+const blink::WebCoalescedInputEvent&
+ScopedWebInputEventWithLatencyInfo::coalesced_event() const {
   return *event_;
 }
 
-blink::WebInputEvent& ScopedWebInputEventWithLatencyInfo::event() {
-  return *event_;
-}
-
 }  // namespace content