Simplify insertion of text track container

Source/core/html/shadow/MediaControls.cpp

Index: Source/core/html/shadow/MediaControls.cpp
diff --git a/Source/core/html/shadow/MediaControls.cpp b/Source/core/html/shadow/MediaControls.cpp
index 4c693c5c3e338a5f0f0062a53912d7e09f8d151a..d5a7aa83e4c5ef7f7ed781dc509d4231e873f5d8 100644
--- a/Source/core/html/shadow/MediaControls.cpp
+++ b/Source/core/html/shadow/MediaControls.cpp
@@ -541,10 +541,7 @@ void MediaControls::createTextTrackDisplay()
     m_textDisplayContainer = textDisplayContainer.get();
 
     // Insert it before (behind) all other control elements.
-    if (m_overlayPlayButton)
-        m_overlayEnclosure->insertBefore(textDisplayContainer.release(), m_overlayPlayButton);
-    else
-        m_overlayEnclosure->insertBefore(textDisplayContainer.release(), m_overlayCastButton);
+    m_overlayEnclosure->insertBefore(textDisplayContainer.release(), m_overlayEnclosure->firstChild());
 }
 
 void MediaControls::showTextTrackDisplay()