Give MainThreadEventQueue a mutable WebInputEvent.

content/renderer/input/main_thread_event_queue.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/renderer/input/main_thread_event_queue.h"
 #include "content/common/input/event_with_latency_info.h"
 #include "content/common/input_messages.h"
 
 namespace content {
 
 EventWithDispatchType::EventWithDispatchType(
-    const blink::WebInputEvent& event,
+    ScopedWebInputEvent event,
     const ui::LatencyInfo& latency,
     InputEventDispatchType dispatch_type)
-    : ScopedWebInputEventWithLatencyInfo(event, latency),
+    : ScopedWebInputEventWithLatencyInfo(std::move(event), latency),
       dispatch_type_(dispatch_type) {}
 
 EventWithDispatchType::~EventWithDispatchType() {}
 
 bool EventWithDispatchType::CanCoalesceWith(
     const EventWithDispatchType& other) const {
   return other.dispatch_type_ == dispatch_type_ &&
          ScopedWebInputEventWithLatencyInfo::CanCoalesceWith(other);
 }
 
@@ skipping 13 matching lines @@
     MainThreadEventQueueClient* client,
     const scoped_refptr<base::SingleThreadTaskRunner>& main_task_runner)
     : routing_id_(routing_id),
       client_(client),
       is_flinging_(false),
       main_task_runner_(main_task_runner) {}
 
 MainThreadEventQueue::~MainThreadEventQueue() {}
 
 bool MainThreadEventQueue::HandleEvent(
-    const blink::WebInputEvent* event,
+    ScopedWebInputEvent event,
     const ui::LatencyInfo& latency,
     InputEventDispatchType original_dispatch_type,
     InputEventAckState ack_result) {
   DCHECK(original_dispatch_type == DISPATCH_TYPE_BLOCKING ||
          original_dispatch_type == DISPATCH_TYPE_NON_BLOCKING);
   DCHECK(ack_result == INPUT_EVENT_ACK_STATE_SET_NON_BLOCKING ||
          ack_result == INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
 
   bool non_blocking = original_dispatch_type == DISPATCH_TYPE_NON_BLOCKING ||
                       ack_result == INPUT_EVENT_ACK_STATE_SET_NON_BLOCKING;
 
   InputEventDispatchType dispatch_type =
       non_blocking ? DISPATCH_TYPE_NON_BLOCKING : DISPATCH_TYPE_BLOCKING;
 
   bool is_wheel = event->type == blink::WebInputEvent::MouseWheel;
   bool is_touch = blink::WebInputEvent::isTouchEventType(event->type);
 
-  std::unique_ptr<EventWithDispatchType> cloned_event(
-      new EventWithDispatchType(*event, latency, dispatch_type));
-
   if (is_touch) {
-    blink::WebTouchEvent& touch_event =
-        static_cast<blink::WebTouchEvent&>(cloned_event->event());
-    touch_event.dispatchedDuringFling = is_flinging_;
+    blink::WebTouchEvent* touch_event =
+        static_cast<blink::WebTouchEvent*>(event.get());
+    touch_event->dispatchedDuringFling = is_flinging_;
     // Adjust the |dispatchType| on the event since the compositor
     // determined all event listeners are passive.
     if (non_blocking) {
-      touch_event.dispatchType =
+      touch_event->dispatchType =
           blink::WebInputEvent::ListenersNonBlockingPassive;
     }
   }
   if (is_wheel && non_blocking) {
     // Adjust the |dispatchType| on the event since the compositor
     // determined all event listeners are passive.
-    static_cast<blink::WebMouseWheelEvent&>(cloned_event->event())
-        .dispatchType = blink::WebInputEvent::ListenersNonBlockingPassive;
+    static_cast<blink::WebMouseWheelEvent*>(event.get())
+        ->dispatchType = blink::WebInputEvent::ListenersNonBlockingPassive;
   }
 
-  QueueEvent(std::move(cloned_event));
+  std::unique_ptr<EventWithDispatchType> event_with_dispatch_type(
+      new EventWithDispatchType(std::move(event), latency, dispatch_type));
+
+  QueueEvent(std::move(event_with_dispatch_type));
 
   // send an ack when we are non-blocking.
   return non_blocking;
 }
 
 void MainThreadEventQueue::PopEventOnMainThread() {
   {
     base::AutoLock lock(event_queue_lock_);
     if (!events_.empty())
       in_flight_event_ = events_.Pop();
@@ skipping 36 matching lines @@
     base::AutoLock lock(event_queue_lock_);
     size_t size_before = events_.size();
     events_.Queue(std::move(event));
     send_notification = events_.size() != size_before;
   }
   if (send_notification)
     SendEventNotificationToMainThread();
 }
 
 }  // namespace content