Add webkitFullscreenElement to Closure's html5 definitions. webkitCurrentFullScreenElement is not set when a cross-domain element is the fullscreened element. webkitFullscreenElement is set to the iframe containing the cross-domain element.

webkitFullscreenElement also seems to be closer to the w3c spec - but I don't know anything about the history here.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66341259

Author: blickly

externs/html5.js

@@ -3022,6 +3022,9 @@ Document.prototype.webkitCancelFullScreen = function() {};
 /** @type {Element} */
 Document.prototype.webkitCurrentFullScreenElement;
 
+/** @type {Element} */
+Document.prototype.webkitFullscreenElement;
+
 /** @type {boolean} */
 Document.prototype.webkitFullScreenKeyboardInputAllowed;