Media Controls: Use events to update controls for closed captions.

third_party/WebKit/Source/core/html/shadow/MediaControls.h

Index: third_party/WebKit/Source/core/html/shadow/MediaControls.h
diff --git a/third_party/WebKit/Source/core/html/shadow/MediaControls.h b/third_party/WebKit/Source/core/html/shadow/MediaControls.h
index f21bf2cb3febe2a4abd30c91dfac9babde8eb25e..e9383312db0b5877c7d51245747b34f59ddddf8f 100644
--- a/third_party/WebKit/Source/core/html/shadow/MediaControls.h
+++ b/third_party/WebKit/Source/core/html/shadow/MediaControls.h
@@ -53,8 +53,6 @@ class CORE_EXPORT MediaControls final : public HTMLDivElement {
 
   void updateCurrentTimeDisplay();
 
-  void changedClosedCaptionsVisibility();
-  void refreshClosedCaptionsButtonVisibility();
   void toggleTextTrackList();
   void showTextTrackAtIndex(unsigned indexToEnable);
   void disableShowingTextTracks();
@@ -95,6 +93,11 @@ class CORE_EXPORT MediaControls final : public HTMLDivElement {
 
   bool overflowMenuVisible();
 
+  // TODO(mlamouri): this is temporary to notify the controls that an
+  // HTMLTrackElement failed to load because there is no web exposed way to
+  // be notified on the TextTrack object. See https://crbug.com/669977
+  void onTrackElementFailedToLoad() { onTextTracksAddedRemoved(); }
+
   DECLARE_VIRTUAL_TRACE();
 
  private:
@@ -148,6 +151,8 @@ class CORE_EXPORT MediaControls final : public HTMLDivElement {
   void onTimeUpdate();
   void onPlay();
   void onPause();
+  void onTextTracksAddedRemoved();

[Zhiqiang Zhang (Slow), 2016/12/01 12:20:46]

nit: s/AddedRemoved/AddedOrRemoved?

[mlamouri (slow - plz ping), 2016/12/01 22:22:54]

Done.

+  void onTextTracksChanged();
 
   Member<HTMLMediaElement> m_mediaElement;