Support subtitles for native fullscreen video

Source/core/page/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 3375 matching lines @@
     if (frame().document())
         return frame().document()->existingAXObjectCache();
     return 0;
 }
 
 bool FrameView::isMainFrame() const
 {
     return m_frame->page() && m_frame->page()->mainFrame() == m_frame;
 }
 
+void FrameView::setCurrentFullscreenRenderer(RenderObject* renderer)
+{
+    ASSERT(isMainFrame());
+    if (RenderView* renderView = this->renderView())

[esprehn, 2013/09/13 02:46:07]

Going through here if there's no RenderView sounds like a bug, you can
ASSERT(renderView()) if you want, but null checking it doesn't look right.

[trchen, 2013/09/13 05:14:58]

This can happen during frame destruction. RenderView get detached before
everything else.

+        renderView->compositor()->setCurrentFullscreenRenderer(renderer);
+}
+
 } // namespace WebCore