Oilpan: prevent player from accessing its media element during finalization

Source/platform/graphics/media/MediaPlayer.h

Index: Source/platform/graphics/media/MediaPlayer.h
diff --git a/Source/platform/graphics/media/MediaPlayer.h b/Source/platform/graphics/media/MediaPlayer.h
index a8fe49d367c14ebd28f49e5a63658ed121bc9d25..130f01562891ac86e57ad323f17c8bfa1b4354d6 100644
--- a/Source/platform/graphics/media/MediaPlayer.h
+++ b/Source/platform/graphics/media/MediaPlayer.h
@@ -95,6 +95,7 @@ public:
     virtual void mediaPlayerDidRemoveTextTrack(blink::WebInbandTextTrack*) = 0;
 
     virtual void mediaPlayerMediaSourceOpened(blink::WebMediaSource*) = 0;
+
 };
 
 typedef PassOwnPtr<MediaPlayer> (*CreateMediaEnginePlayer)(MediaPlayerClient*);
@@ -110,6 +111,8 @@ public:
     MediaPlayer() { }
     virtual ~MediaPlayer() { }
 
+    virtual void detach() = 0;
+
     virtual void load(blink::WebMediaPlayer::LoadType, const String& url, blink::WebMediaPlayer::CORSMode) = 0;
 
     virtual void play() = 0;
@@ -163,6 +166,7 @@ public:
     virtual AudioSourceProvider* audioSourceProvider() = 0;
 #endif
     virtual blink::WebMediaPlayer* webMediaPlayer() const = 0;
+
 };
 
 }