Start separating the text track container from the media controls

Source/core/layout/LayoutMediaControls.cpp

 /*
  * Copyright (C) 2009 Apple Inc.
  * 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 383 matching lines @@
     case MediaCastOnButton:
     case MediaOverlayCastOffButton:
     case MediaOverlayCastOnButton:
         return paintMediaCastButton(object, paintInfo, rect);
     case MediaVolumeSliderContainer:
     case MediaTimelineContainer:
     case MediaCurrentTimeDisplay:
     case MediaTimeRemainingDisplay:
     case MediaControlsPanel:
     case MediaHideClosedCaptionsButton:
-    case MediaTextTrackDisplayContainer:
     case MediaFullScreenVolumeSlider:
     case MediaFullScreenVolumeSliderThumb:
         ASSERT_NOT_REACHED();
         break;
     }
     return false;
 }
 
 const int mediaSliderThumbHeight = 24;
 const int mediaVolumeSliderThumbHeight = 24;
@@ skipping 51 matching lines @@
 {
     return formatChromiumMediaControlsTime(time, time);
 }
 
 String LayoutMediaControls::formatMediaControlsCurrentTime(float currentTime, float duration)
 {
     return formatChromiumMediaControlsTime(currentTime, duration);
 }
 
 } // namespace blink