Remove default implementation of WebMediaPlayer::seekable()

public/platform/WebMediaPlayer.h

 /*
  * Copyright (C) 2009 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 96 matching lines @@
     virtual void play() = 0;
     virtual void pause() = 0;
     virtual bool supportsSave() const = 0;
     virtual void seek(double seconds) = 0;
     virtual void setRate(double) = 0;
     virtual void setVolume(double) = 0;
     virtual void requestRemotePlayback() { };
     virtual void requestRemotePlaybackControl() { };
     virtual void setPreload(Preload) { };
     virtual WebTimeRanges buffered() const = 0;
-    virtual WebTimeRanges seekable() const
-    {
-        if (double end = maxTimeSeekable()) {
-            WebTimeRanges ranges(static_cast<size_t>(1));
-            ranges[0].start = 0.0;
-            ranges[0].end = end;
-            return ranges;
-        }
-        return WebTimeRanges();
-    }
-    virtual double maxTimeSeekable() const { return 0.0; }
+    virtual WebTimeRanges seekable() const = 0;
 
     // True if the loaded media has a playable video/audio track.
     virtual bool hasVideo() const = 0;
     virtual bool hasAudio() const = 0;
 
     // Dimension of the video.
     virtual WebSize naturalSize() const = 0;
 
     // Getters of playback state.
     virtual bool paused() const = 0;
@@ skipping 40 matching lines @@
     virtual bool canEnterFullscreen() const { return false; }
 
     virtual void enabledAudioTracksChanged(const WebVector<TrackId>& enabledTrackIds) { }
     // |selectedTrackId| is null if no track is selected.
     virtual void selectedVideoTrackChanged(TrackId* selectedTrackId) { }
 };
 
 } // namespace blink
 
 #endif