Support text track selection in video controls

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

Index: third_party/WebKit/Source/core/html/shadow/MediaControlElements.h
diff --git a/third_party/WebKit/Source/core/html/shadow/MediaControlElements.h b/third_party/WebKit/Source/core/html/shadow/MediaControlElements.h
index f2e3a42bbce5011f58cee89c07c77deb4463528a..e11abcf8b939980c1523d24cd7fe09b71ef6440a 100644
--- a/third_party/WebKit/Source/core/html/shadow/MediaControlElements.h
+++ b/third_party/WebKit/Source/core/html/shadow/MediaControlElements.h
@@ -34,6 +34,8 @@
 
 namespace blink {
 
+class TextTrack;
+
 // ----------------------------
 
 class MediaControlPanelElement final : public MediaControlDivElement {
@@ -146,6 +148,33 @@ private:
 
 // ----------------------------
 
+class MediaControlTextTrackListElement final : public MediaControlDivElement {
+public:
+    static RawPtr<MediaControlTextTrackListElement> create(MediaControls&);
+
+    bool willRespondToMouseClickEvents() override { return true; }
+
+    void setVisible(bool);
+
+private:
+    explicit MediaControlTextTrackListElement(MediaControls&);
+
+    void defaultEventHandler(Event*) override;
+
+    void refreshTextTrackListMenu();
+
+    bool shouldDisplayTrackKindMarker(TextTrack*, String);
+    // Returns the label for the track when a valid track is passed in and "Off" when the parameter is null.
+    String getTextTrackLabel(TextTrack*);
+    // Creates the track element in the list when a valid track is passed in and the "Off" item when the parameter is null.
+    RawPtr<Element> createTextTrackListItem(TextTrack*);
+
+    void showTextTrackAtIndex(unsigned);
+    void disableShowingTextTracks();
+};
+
+// ----------------------------
+
 class MediaControlTimelineElement final : public MediaControlInputElement {
 public:
     static RawPtr<MediaControlTimelineElement> create(MediaControls&);