Better fullscreen handling for Chrome OS Video Player

chrome/browser/resources/file_manager/js/mock_chrome.js

Index: chrome/browser/resources/file_manager/js/mock_chrome.js
diff --git a/chrome/browser/resources/file_manager/js/mock_chrome.js b/chrome/browser/resources/file_manager/js/mock_chrome.js
index 8a80d18fb316442f0c0a2a2fc3a94ce3eb476805..246fa2ee4586ca9073a1d20ef3ffcf6b318c1db6 100644
--- a/chrome/browser/resources/file_manager/js/mock_chrome.js
+++ b/chrome/browser/resources/file_manager/js/mock_chrome.js
@@ -259,6 +259,17 @@ chrome.fileBrowserPrivate = {
     callback(metadata);
   },
 
+  toggleFullscreen: function() {
+    if (document.webkitIsFullScreen)
+      document.webkitCancelFullScreen();
+    else
+      document.body.webkitRequestFullScreen();
+  },
+
+  isFullscreen: function(callback) {
+    setTimeout(callback, 0, document.webkitIsFullScreen);
+  },
+
   /**
    * Return localized strings.
    */