Hook up Android closed captions 'enabled' setting to Blink

Source/core/dom/Document.h

Index: Source/core/dom/Document.h
diff --git a/Source/core/dom/Document.h b/Source/core/dom/Document.h
index 89d1fb7a6d7b1a704eb21bf0c220d6c2c00fc292..5974d3a910af579ad5edc51b7b64ad98eb7d2d85 100644
--- a/Source/core/dom/Document.h
+++ b/Source/core/dom/Document.h
@@ -117,6 +117,7 @@ class HTMLHeadElement;
 class HTMLImportLoader;
 class HTMLImportsController;
 class HTMLLinkElement;
+class HTMLMediaElement;
 class HTMLScriptElement;
 class HitTestRequest;
 class LayoutPoint;
@@ -237,6 +238,10 @@ public:
 
     void mediaQueryAffectingValueChanged();
 
+    void registerForTextTracksVisibilityChangedCallback(HTMLMediaElement*);
+    void unregisterFromTextTracksVisibilityChangedCallback(HTMLMediaElement*);
+    void textTracksVisibilityChanged(bool visible);
+
 #if !ENABLE(OILPAN)
     using ContainerNode::ref;
     using ContainerNode::deref;
@@ -1411,6 +1416,8 @@ private:
     ParserSynchronizationPolicy m_parserSyncPolicy;
 
     OriginsUsingFeatures::Value m_originsUsingFeaturesValue;
+
+    Vector<HTMLMediaElement*> m_textTracksVisibilityChangedElements;

[tkent, 2015/04/29 23:58:44]

Setting change won't happen so frequently, and doesn't need to be fast.
Please don't keep the list of HTMLMediaElement.

[srivats, 2015/05/01 23:03:31]

Done.

 };
 
 inline bool Document::shouldOverrideLegacyDescription(ViewportDescription::Type origin)