Support text track selection in video controls

third_party/WebKit/Source/core/html/track/TextTrack.h

Index: third_party/WebKit/Source/core/html/track/TextTrack.h
diff --git a/third_party/WebKit/Source/core/html/track/TextTrack.h b/third_party/WebKit/Source/core/html/track/TextTrack.h
index d2ec84c2bd41cf545b156c23ab377fef75ce7930..eba68469af1af4e3a8588b631e873280073e8f0e 100644
--- a/third_party/WebKit/Source/core/html/track/TextTrack.h
+++ b/third_party/WebKit/Source/core/html/track/TextTrack.h
@@ -56,7 +56,7 @@ public:
     ~TextTrack() override;
 
     virtual void setTrackList(TextTrackList*);
-    TextTrackList* trackList() { return m_trackList; }
+    TextTrackList* trackList() const { return m_trackList; }
 
     void setKind(const AtomicString&) override;
 
@@ -102,7 +102,8 @@ public:
     int trackIndex();
     void invalidateTrackIndex();
 
-    bool isRendered();
+    bool isRendered() const;
+    bool canBeRendered() const;
     int trackIndexRelativeToRenderedTracks();
 
     bool hasBeenConfigured() const { return m_hasBeenConfigured; }