Keep track of coalesced events in main thread event queue

content/common/input/event_with_latency_info.cc

Index: content/common/input/event_with_latency_info.cc
diff --git a/content/common/input/event_with_latency_info.cc b/content/common/input/event_with_latency_info.cc
index 79084e5aa128bc67706f566581f503bb56748337..d4ea6731bc9e04f671cf0dc6b32c1762ac0d4f5b 100644
--- a/content/common/input/event_with_latency_info.cc
+++ b/content/common/input/event_with_latency_info.cc
@@ -11,7 +11,8 @@ 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() {}
 
@@ -29,8 +30,9 @@ void ScopedWebInputEventWithLatencyInfo::CoalesceWith(
   // 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.
@@ -39,10 +41,15 @@ void ScopedWebInputEventWithLatencyInfo::CoalesceWith(
 }
 
 const blink::WebInputEvent& ScopedWebInputEventWithLatencyInfo::event() const {
-  return *event_;
+  return event_->event();
 }
 
 blink::WebInputEvent& ScopedWebInputEventWithLatencyInfo::event() {
+  return *event_->eventPointer();
+}
+
+const blink::WebCoalescedInputEvent&
+ScopedWebInputEventWithLatencyInfo::coalesced_event() const {
   return *event_;
 }