[Video] MediaSession API event handlers can resume background video.

third_party/WebKit/Source/core/html/HTMLMediaElement.h

 /*
  * Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple 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 375 matching lines @@
   void removeVideoTrack(WebMediaPlayer::TrackId) final;
   void addTextTrack(WebInbandTextTrack*) final;
   void removeTextTrack(WebInbandTextTrack*) final;
   void mediaSourceOpened(WebMediaSource*) final;
   void requestSeek(double) final;
   void remoteRouteAvailabilityChanged(WebRemotePlaybackAvailability) final;
   void connectedToRemoteDevice() final;
   void disconnectedFromRemoteDevice() final;
   void cancelledRemotePlaybackRequest() final;
   void remotePlaybackStarted() final;
+  void wasPausedWhenBackgrounded() final;
+  void wasResumedWhenForegrounded() final;
   bool hasSelectedVideoTrack() final;
   WebMediaPlayer::TrackId getSelectedVideoTrackId() final;
   bool isAutoplayingMuted() final;
   void requestReload(const WebURL&) final;
   void activateViewportIntersectionMonitoring(bool) final;
+  bool isBackgroundVideoPlaybackUnlocked() final;
 
   void loadTimerFired(TimerBase*);
   void progressEventTimerFired(TimerBase*);
   void playbackProgressTimerFired(TimerBase*);
   void checkViewportIntersectionTimerFired(TimerBase*);
   void startPlaybackProgressTimer();
   void startProgressEventTimer();
   void stopPeriodicTimers();
 
   void seek(double time);
@@ skipping 216 matching lines @@
   mutable bool m_officialPlaybackPositionNeedsUpdate;
 
   double m_fragmentEndTime;
 
   typedef unsigned PendingActionFlags;
   PendingActionFlags m_pendingActionFlags;
 
   // FIXME: HTMLMediaElement has way too many state bits.
   bool m_lockedPendingUserGesture : 1;
   bool m_lockedPendingUserGestureIfCrossOriginExperimentEnabled : 1;
+  bool m_wasLockedWhenBackgrounded : 1;
   bool m_playing : 1;
   bool m_shouldDelayLoadEvent : 1;
   bool m_haveFiredLoadedData : 1;
   bool m_canAutoplay : 1;
   bool m_muted : 1;
   bool m_paused : 1;
   bool m_seeking : 1;
 
   // data has not been loaded since sending a "stalled" event
   bool m_sentStalledEvent : 1;
@@ skipping 103 matching lines @@
 
 inline bool isHTMLMediaElement(const HTMLElement& element) {
   return isHTMLAudioElement(element) || isHTMLVideoElement(element);
 }
 
 DEFINE_HTMLELEMENT_TYPE_CASTS_WITH_FUNCTION(HTMLMediaElement);
 
 }  // namespace blink
 
 #endif  // HTMLMediaElement_h