Teach main thread event queue about closures.

content/common/input/web_input_event_queue.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 CONTENT_COMMON_INPUT_WEB_INPUT_EVENT_QUEUE_H_

[mustaq, 2017/03/24 15:31:18]

Should we move this source file to content/renderer/input?

[dtapuska, 2017/03/24 20:16:31]

Hmm; ya I could clean this up.

 #define CONTENT_COMMON_INPUT_WEB_INPUT_EVENT_QUEUE_H_
 
 #include <deque>
 #include <memory>
 
 namespace content {
 
 // WebInputEventQueue is a coalescing queue. It will examine
 // the current events in the queue and will attempt to coalesce with
 // the last event of the same class type.
 template <typename T>
 class WebInputEventQueue {
  public:
   WebInputEventQueue() {}
 
   // Adds an event to the queue. The event may be coalesced with previously
   // queued events.
   void Queue(std::unique_ptr<T> event) {
     for (auto last_event_iter = queue_.rbegin();
          last_event_iter != queue_.rend(); ++last_event_iter) {
-      if (!(*last_event_iter)->event().isSameEventClass(event->event())) {
+      if (!(*last_event_iter)->IsSameEventClass(*event.get())) {
         continue;
       }
 
       if ((*last_event_iter)->CanCoalesceWith(*event.get())) {
         (*last_event_iter)->CoalesceWith(*event.get());
         return;
       }
       break;
     }
     queue_.emplace_back(std::move(event));
   }
 
   const std::unique_ptr<T>& front() const { return queue_.front(); }
   const std::unique_ptr<T>& at(size_t pos) const { return queue_.at(pos); }
 
   std::unique_ptr<T> Pop() {

[mustaq, 2017/03/24 15:31:18]

Nit: make it |pop()| to be consistent?

[dtapuska, 2017/03/24 20:16:31]

Not done because I've made this no longer a templated class and it has a
non-trivial implementation so it has a capital according to the style guide.

     std::unique_ptr<T> result;
     if (!queue_.empty()) {
       result.reset(queue_.front().release());
       queue_.pop_front();
     }
     return result;
   }
 
+  void emplace_front(std::unique_ptr<T> event) {
+    queue_.emplace_front(std::move(event));
+  }
+  void swap(std::deque<std::unique_ptr<T>>* queue) { queue_.swap(*queue); }
+
   bool empty() const { return queue_.empty(); }
 
   size_t size() const { return queue_.size(); }
 
  private:
   typedef std::deque<std::unique_ptr<T>> EventQueue;
   EventQueue queue_;
 
   DISALLOW_COPY_AND_ASSIGN(WebInputEventQueue);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_INPUT_WEB_INPUT_EVENT_QUEUE_H_