Implement media cast buttons

Source/core/html/shadow/MediaControls.h

Index: Source/core/html/shadow/MediaControls.h
diff --git a/Source/core/html/shadow/MediaControls.h b/Source/core/html/shadow/MediaControls.h
index 21c767ae56e91e6bcacca6691607cfd461f32429..dc2b7029ace4d8863fc9eaaf211b86c9d1bdfd9a 100644
--- a/Source/core/html/shadow/MediaControls.h
+++ b/Source/core/html/shadow/MediaControls.h
@@ -64,6 +64,11 @@ public:
     void enteredFullscreen();
     void exitedFullscreen();
 
+    void startedCasting();
+    void stoppedCasting();
+    void refreshCastButtonVisibility();
+    void showOverlayCastButton();
+
     void updateTextTrackDisplay();
 
     void mediaElementFocused();
@@ -89,6 +94,7 @@ private:
     void hideMediaControlsTimerFired(Timer<MediaControls>*);
     void startHideMediaControlsTimer();
     void stopHideMediaControlsTimer();
+    void resetHideMediaControlsTimer();
 
     void createTextTrackDisplay();
     void showTextTrackDisplay();
@@ -121,6 +127,8 @@ private:
     RawPtrWillBeMember<MediaControlVolumeSliderElement> m_volumeSlider;
     RawPtrWillBeMember<MediaControlToggleClosedCaptionsButtonElement> m_toggleClosedCaptionsButton;
     RawPtrWillBeMember<MediaControlFullscreenButtonElement> m_fullScreenButton;
+    RawPtrWillBeMember<MediaControlCastButtonElement> m_castButton;
+    RawPtrWillBeMember<MediaControlCastButtonElement> m_overlayCastButton;
     RawPtrWillBeMember<MediaControlTimeRemainingDisplayElement> m_durationDisplay;
     RawPtrWillBeMember<MediaControlPanelEnclosureElement> m_enclosure;