Adds keyboard functionality for videos.

third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.h

 /*
  * Copyright (C) 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 107 matching lines @@
   void onTimeUpdate() override;
   void onDurationChange() override;
   void onPlay() override;
   void onPause() override;
   void onTextTracksAddedOrRemoved() override;
   void onTextTracksChanged() override;
   void onError() override;
   void onLoadedMetadata() override;
   void onEnteredFullscreen() override;
   void onExitedFullscreen() override;
+  void onMediaKeyboardEvent(Event* event) { defaultEventHandler(event); }
   Document& ownerDocument() { return document(); }
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   friend class MediaControlsMediaEventListener;
   friend class MediaControlsOrientationLockDelegateTest;
   friend class MediaControlsImplTest;
 
   // Need to be members of MediaControls for private member access.
@@ skipping 91 matching lines @@
   IntSize m_size;
 
   bool m_keepShowingUntilTimerFires : 1;
 };
 
 DEFINE_ELEMENT_TYPE_CASTS(MediaControlsImpl, isMediaControls());
 
 }  // namespace blink
 
 #endif