Support text track selection in video controls

Source/platform/ThemeTypes.h

Index: Source/platform/ThemeTypes.h
diff --git a/Source/platform/ThemeTypes.h b/Source/platform/ThemeTypes.h
index ba8805f861f4d924f3e4cbd80c4418f8d0ce3ff8..21f5f2ff141e64e5bef22288e1fb58e9f68e6186 100644
--- a/Source/platform/ThemeTypes.h
+++ b/Source/platform/ThemeTypes.h
@@ -50,7 +50,8 @@ enum ControlPart {
     MediaEnterFullscreenButtonPart, MediaExitFullscreenButtonPart, MediaFullScreenVolumeSliderPart, MediaFullScreenVolumeSliderThumbPart, MediaMuteButtonPart, MediaPlayButtonPart,
     MediaOverlayPlayButtonPart, MediaToggleClosedCaptionsButtonPart,
     MediaSliderPart, MediaSliderThumbPart, MediaVolumeSliderContainerPart, MediaVolumeSliderPart, MediaVolumeSliderThumbPart,
-    MediaControlsBackgroundPart, MediaControlsFullscreenBackgroundPart, MediaCurrentTimePart, MediaTimeRemainingPart, MediaCastOffButtonPart, MediaOverlayCastOffButtonPart,
+    MediaControlsBackgroundPart, MediaControlsFullscreenBackgroundPart, MediaCurrentTimePart, MediaTimeRemainingPart, MediaTrackSelectionCheckmarkPart,
+    MediaCastOffButtonPart, MediaOverlayCastOffButtonPart,
     MenulistPart, MenulistButtonPart, MenulistTextPart, MenulistTextFieldPart, MeterPart, ProgressBarPart, ProgressBarValuePart,
     SliderHorizontalPart, SliderVerticalPart, SliderThumbHorizontalPart,
     SliderThumbVerticalPart, CaretPart, SearchFieldPart, SearchFieldDecorationPart,