[Web Intents] Display throbber when loading inline disposition.

chrome/browser/ui/intents/web_intent_picker.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_INTENTS_WEB_INTENT_PICKER_H_
 #define CHROME_BROWSER_UI_INTENTS_WEB_INTENT_PICKER_H_
 #pragma once
 
 #include <stddef.h>
 #include <vector>
@@ skipping 24 matching lines @@
   // Called when an extension is successfully installed via the picker.
   virtual void OnExtensionInstallSuccess(const std::string& id) {}
 
   // Called when an extension installation started via the picker has failed.
   virtual void OnExtensionInstallFailure(const std::string& id) {}
 
   // Called when the controller has finished all pending asynchronous
   // activities.
   virtual void OnPendingAsyncCompleted() {}
 
+  // Called when the inline disposition's web contents have been loaded.
+  virtual void OnInlineDispositionWebContentsLoaded(
+      content::WebContents* web_contents) {}
+
   // Get the default size of the inline disposition tab container.
   static gfx::Size GetDefaultInlineDispositionSize(
       content::WebContents* web_contents);
 
   // Get the star image IDs to use for the nth star (out of 5), given a
   // |rating| in the range [0, 5].
   static int GetNthStarImageIdFromCWSRating(double rating, int index);
 
  protected:
   virtual ~WebIntentPicker() {}
 };
 
 #endif  // CHROME_BROWSER_UI_INTENTS_WEB_INTENT_PICKER_H_