[Compositor event queue] Coalesce gesture scroll&pinch of the same sequence

ui/events/blink/event_with_callback.h

 // 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.
 
 #ifndef UI_EVENTS_BLINK_EVENT_WITH_CALLBACK_H_
 #define UI_EVENTS_BLINK_EVENT_WITH_CALLBACK_H_
 
 #include <list>
 
 #include "ui/events/blink/input_handler_proxy.h"
 #include "ui/events/latency_info.h"
 
 namespace ui {
 
 namespace test {
 class InputHandlerProxyEventQueueTest;
 }
 
 class EventWithCallback {
  public:
+  struct OriginalEventWithCallback {
+    OriginalEventWithCallback(
+        ScopedWebInputEvent event,
+        const InputHandlerProxy::EventDispositionCallback& callback);
+    ~OriginalEventWithCallback();
+    ScopedWebInputEvent event_;
+    InputHandlerProxy::EventDispositionCallback callback_;
+  };
+  using OriginalEventList = std::list<OriginalEventWithCallback>;
+
   EventWithCallback(
       ScopedWebInputEvent event,
       const LatencyInfo& latency,
       base::TimeTicks timestamp_now,
       const InputHandlerProxy::EventDispositionCallback& callback);
+  EventWithCallback(ScopedWebInputEvent event,
+                    const LatencyInfo& latency,
+                    base::TimeTicks creation_timestamp,
+                    base::TimeTicks last_coalesced_timestamp,
+                    std::unique_ptr<OriginalEventList> original_events);
   ~EventWithCallback();
 
   bool CanCoalesceWith(const EventWithCallback& other) const WARN_UNUSED_RESULT;
   void CoalesceWith(EventWithCallback* other, base::TimeTicks timestamp_now);
 
   void RunCallbacks(InputHandlerProxy::EventDisposition,
                     const LatencyInfo& latency,
                     std::unique_ptr<DidOverscrollParams>);
 
   const blink::WebInputEvent& event() const { return *event_; }
   const LatencyInfo latency_info() const { return latency_; }
   base::TimeTicks creation_timestamp() const { return creation_timestamp_; }
   base::TimeTicks last_coalesced_timestamp() const {
     return last_coalesced_timestamp_;
   }
   size_t coalesced_count() const { return original_events_.size(); }
+  OriginalEventList& original_events() { return original_events_; }
 
  private:
   friend class test::InputHandlerProxyEventQueueTest;
-  struct OriginalEventWithCallback {
-    OriginalEventWithCallback(
-        ScopedWebInputEvent event,
-        const InputHandlerProxy::EventDispositionCallback& callback);
-    ~OriginalEventWithCallback();
-    ScopedWebInputEvent event_;
-    InputHandlerProxy::EventDispositionCallback callback_;
-  };
 
   void SetTickClockForTesting(std::unique_ptr<base::TickClock> tick_clock);
 
   ScopedWebInputEvent event_;
   LatencyInfo latency_;
-  std::list<OriginalEventWithCallback> original_events_;
+  OriginalEventList original_events_;
 
   base::TimeTicks creation_timestamp_;
   base::TimeTicks last_coalesced_timestamp_;
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_BLINK_EVENT_WITH_CALLBACK_H_