Start separating the text track container from the media controls

Source/core/html/HTMLMediaElement.cpp

Index: Source/core/html/HTMLMediaElement.cpp
diff --git a/Source/core/html/HTMLMediaElement.cpp b/Source/core/html/HTMLMediaElement.cpp
index 9e4a12733fd5475cf49f5b8794729503c8fc3222..7b7a5223c514b62a99dda086c158fea96596cf46 100644
--- a/Source/core/html/HTMLMediaElement.cpp
+++ b/Source/core/html/HTMLMediaElement.cpp
@@ -55,6 +55,7 @@
 #include "core/html/track/AutomaticTrackSelection.h"
 #include "core/html/track/CueTimeline.h"
 #include "core/html/track/InbandTextTrack.h"
+#include "core/html/track/TextTrackContainer.h"
 #include "core/html/track/TextTrackList.h"
 #include "core/html/track/VideoTrack.h"
 #include "core/html/track/VideoTrackList.h"
@@ -3183,12 +3184,17 @@ bool HTMLMediaElement::closedCaptionsVisible() const
     return m_closedCaptionsVisible;
 }
 
+TextTrackContainer& HTMLMediaElement::ensureTextTrackContainer()
+{
+    ensureMediaControls();
+    return *mediaControls()->textTrackContainer();
+}
+
 void HTMLMediaElement::updateTextTrackDisplay()
 {
     WTF_LOG(Media, "HTMLMediaElement::updateTextTrackDisplay(%p)", this);
 
-    ensureMediaControls();
-    mediaControls()->updateTextTrackDisplay();
+    ensureTextTrackContainer().updateDisplay(*this);
 }
 
 void HTMLMediaElement::setClosedCaptionsVisible(bool closedCaptionVisible)