DevTools: Fix presubmits failing on InspectorFrontendHostAPI

Review-Url: https://codereview.chromium.org/2161033005
Cr-Commit-Position: refs/heads/master@{#406709}

third_party/WebKit/Source/devtools/front_end/host/InspectorFrontendHost.js

@@ -449,15 +449,15 @@ WebInspector.InspectorFrontendHostStub.prototype = {
 /**
  * @type {!InspectorFrontendHostAPI}
  */
-window.InspectorFrontendHost = window.InspectorFrontendHost || null;
-
+var InspectorFrontendHost = window.InspectorFrontendHost || null;
+window.InspectorFrontendHost = InspectorFrontendHost;
 (function(){
 
     function initializeInspectorFrontendHost()
     {
         if (!InspectorFrontendHost) {
             // Instantiate stub for web-hosted mode if necessary.
-            InspectorFrontendHost = new WebInspector.InspectorFrontendHostStub();
+            window.InspectorFrontendHost = InspectorFrontendHost = new WebInspector.InspectorFrontendHostStub();
         } else {
             // Otherwise add stubs for missing methods that are declared in the interface.
             var proto = WebInspector.InspectorFrontendHostStub.prototype;

third_party/WebKit/Source/devtools/front_end/host/InspectorFrontendHostAPI.js

@@ -4,10 +4,10 @@
 
 
 /** @interface */
-window.InspectorFrontendHostAPI = function()
+function InspectorFrontendHostAPI()
 {
 }
-
+window.InspectorFrontendHostAPI = InspectorFrontendHostAPI;
 /** @typedef
 {{
     type: string,