Fix cue rendering test and include support for left/right alignment.

Source/core/html/track/TextTrackCue.h

 /*
  * Copyright (C) 2011 Google Inc.  All rights reserved.
  * Copyright (C) 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 152 matching lines @@
         Horizontal,
         VerticalGrowingLeft,
         VerticalGrowingRight,
         NumberOfWritingDirections
     };
     WritingDirection getWritingDirection() const { return m_writingDirection; }
 
     enum CueAlignment {
         Start,
         Middle,
-        End
+        End,
+        Left,
+        Right
     };
     CueAlignment getAlignment() const { return m_cueAlignment; }
 
     virtual void videoSizeDidChange(const IntSize&) { }
 
     virtual bool operator==(const TextTrackCue&) const;
     virtual bool operator!=(const TextTrackCue& cue) const
     {
         return !(*this == cue);
     }
@@ skipping 89 matching lines @@
 
     std::pair<float, float> m_displayPosition;
 #if ENABLE(WEBVTT_REGIONS)
     String m_regionId;
 #endif
 };
 
 } // namespace WebCore
 
 #endif