[DevTools] Fix more frontend compiler errors

third_party/WebKit/Source/devtools/front_end/extensions/ExtensionAPI.js

 /*
  * Copyright (C) 2012 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 935 matching lines @@
 
 /**
  * @suppress {checkVars, checkTypes}
  */
 function platformExtensionAPI(coreAPI)
 {
     function getTabId()
     {
         return tabId;
     }
-    chrome = window.chrome || {};
+    var chrome = window.chrome || {};
     // Override chrome.devtools as a workaround for a error-throwing getter being exposed
     // in extension pages loaded into a non-extension process (only happens for remote client
     // extensions)
     var devtools_descriptor = Object.getOwnPropertyDescriptor(chrome, "devtools");
     if (!devtools_descriptor || devtools_descriptor.get)
         Object.defineProperty(chrome, "devtools", { value: {}, enumerable: true });
     // Only expose tabId on chrome.devtools.inspectedWindow, not webInspector.inspectedWindow.
     chrome.devtools.inspectedWindow = {};
     chrome.devtools.inspectedWindow.__defineGetter__("tabId", getTabId);
     chrome.devtools.inspectedWindow.__proto__ = coreAPI.inspectedWindow;
@@ skipping 37 matching lines @@
 {
     return "(function(injectedScriptId){ " +
         "var extensionServer;" +
         defineCommonExtensionSymbols.toString() + ";" +
         injectedExtensionAPI.toString() + ";" +
         buildPlatformExtensionAPI(extensionInfo, inspectedTabId) + ";" +
         "platformExtensionAPI(injectedExtensionAPI(injectedScriptId));" +
         "return {};" +
         "})";
 }