Add a method to the controller to close the picker/service tab when a return value is passed.

chrome/browser/ui/intents/web_intent_picker_delegate.h

 // Copyright (c) 2011 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_DELEGATE_H_
 #define CHROME_BROWSER_UI_INTENTS_WEB_INTENT_PICKER_DELEGATE_H_
 #pragma once
 
 // A class used to notify the delegate when the user has chosen a web intent
 // service.
 class WebIntentPickerDelegate {
  public:
   // Base destructor.
   virtual ~WebIntentPickerDelegate() {}
 
   // Callback called when the user has chosen a service.
   virtual void OnServiceChosen(size_t index) = 0;
 
   // Callback called when the user cancels out of the dialog, whether by closing
   // it manually or otherwise purposefully.
   virtual void OnCancelled() = 0;
 
-  // Callback called when the dialog wants to stop showing (can happen by
-  // cancellation or by the user choosing a service).
+  // Callback called when the dialog stops showing.
   virtual void OnClosing() = 0;
 };
 
 #endif  // CHROME_BROWSER_UI_INTENTS_WEB_INTENT_PICKER_DELEGATE_H_