Adds keyboard functionality for videos.

third_party/WebKit/Source/modules/media_controls/elements/MediaControlPlayButtonElement.h

 // Copyright 2017 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 MediaControlPlayButtonElement_h
 #define MediaControlPlayButtonElement_h
 
 #include "core/html/shadow/MediaControlElementTypes.h"
 
 namespace blink {
 
 class Event;
 class MediaControlsImpl;
 
 class MediaControlPlayButtonElement final : public MediaControlInputElement {
  public:
   explicit MediaControlPlayButtonElement(MediaControlsImpl&);
 
   // MediaControlInputElement overrides.
   bool WillRespondToMouseClickEvents() override;
   void UpdateDisplayType() override;
   WebLocalizedString::Name GetOverflowStringName() override;
   bool HasOverflowButton() override;
 
+  void OnMediaKeyboardEvent(Event* event) { DefaultEventHandler(event); }
+
  private:
   void DefaultEventHandler(Event*) override;
 };
 
 }  // namespace blink
 
 #endif  // MediaControlPlayButtonElement_h