Support subtitles for native fullscreen video

Source/web/WebViewImpl.h

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 544 matching lines @@
     WebSettingsImpl* settingsImpl();
 
     // Returns the bounding box of the block type node touched by the WebRect.
     WebRect computeBlockBounds(const WebRect&, bool ignoreClipping);
 
     WebCore::IntPoint clampOffsetAtScale(const WebCore::IntPoint& offset, float scale);
 
     // Exposed for tests.
     WebVector<WebCompositionUnderline> compositionUnderlines() const;
 
+    WebLayerTreeView* layerTreeView() const { return m_layerTreeView; };
+
 private:
     float legibleScale() const;
     void refreshPageScaleFactorAfterLayout();
     void setUserAgentPageScaleConstraints(WebCore::PageScaleConstraints newConstraints);
     float clampPageScaleFactorToLimits(float) const;
     WebCore::IntSize contentsSize() const;
 
     void resetSavedScrollAndScaleState();
 
     void updateMainFrameScrollPosition(const WebCore::IntPoint& scrollPosition, bool programmaticScroll);
@@ skipping 255 matching lines @@
 inline WebViewImpl* toWebViewImpl(WebView* webView)
 {
     // We have no ways to check if the specified WebView is an instance of
     // WebViewImpl because WebViewImpl is the only implementation of WebView.
     return static_cast<WebViewImpl*>(webView);
 }
 
 } // namespace WebKit
 
 #endif