Adds the UserInputMonitor implementation for Mac.

media/base/user_input_monitor.h

 // Copyright 2013 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 MEDIA_BASE_USER_INPUT_MONITOR_H_
 #define MEDIA_BASE_USER_INPUT_MONITOR_H_
 
 #include <set>
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "base/synchronization/lock.h"
 #include "media/base/media_export.h"
 #include "ui/base/events/event_constants.h"
 #include "ui/base/keycodes/keyboard_codes.h"
 
 struct SkIPoint;
 
 namespace base {
 class SingleThreadTaskRunner;
@@ skipping 52 matching lines @@
   // listeners.
   void OnMouseEvent(const SkIPoint& position);
   void OnKeyboardEvent(ui::EventType event, ui::KeyboardCode key_code);
 
  private:
   virtual void StartMouseMonitoring() = 0;
   virtual void StopMouseMonitoring() = 0;
   virtual void StartKeyboardMonitoring() = 0;
   virtual void StopKeyboardMonitoring() = 0;
 
+  // Polling the key state perodically on Mac.
+  void PollKeyState();
+
   base::Lock lock_;
   ObserverList<MouseEventListener, true> mouse_listeners_;
   ObserverList<KeyStrokeListener, true> key_stroke_listeners_;
   bool monitoring_mouse_;
   bool monitoring_keyboard_;
   // The set of keys currently held down. Used for convering raw keyboard events
   // into KeyStrokeListener callbacks.
-  std::set<ui::KeyboardCode> pressed_keys_;
+  std::set<int> pressed_keys_;
 
   DISALLOW_COPY_AND_ASSIGN(UserInputMonitor);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_USER_INPUT_MONITOR_H_