Fix memory management of VoiceSearchBarView.

ios/public/provider/chrome/browser/voice/voice_search_provider.h

 // Copyright 2016 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 IOS_PUBLIC_PROVIDER_CHROME_BROWSER_VOICE_VOICE_SEARCH_PROVIDER_H_
 #define IOS_PUBLIC_PROVIDER_CHROME_BROWSER_VOICE_VOICE_SEARCH_PROVIDER_H_
 
 #import <Foundation/Foundation.h>
 #import <UIKit/UIKit.h>
 
@@ skipping 23 matching lines @@
   virtual NSArray* GetAvailableLanguages() const;
 
   // Returns the singleton audio session controller.
   virtual AudioSessionController* GetAudioSessionController() const;
 
   // Creates a new VoiceSearchController object.
   virtual scoped_refptr<VoiceSearchController> CreateVoiceSearchController(
       ios::ChromeBrowserState* browser_state) const;
 
   // Creates a new VoiceSearchBar.  The caller assumes ownership.
+  // TODO(crbug.com/679719): Remove this once downstream provider implementaiton
+  // switches to BuildVoiceSearchBar().
   virtual UIView<VoiceSearchBar>* CreateVoiceSearchBar(CGRect frame) const
       NS_RETURNS_RETAINED;
 
+  // Creates a new VoiceSearchBar.  Returns an autoreleased view.
+  virtual UIView<VoiceSearchBar>* BuildVoiceSearchBar(CGRect frame) const;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(VoiceSearchProvider);
 };
 
 #endif  // IOS_PUBLIC_PROVIDER_CHROME_BROWSER_VOICE_VOICE_SEARCH_PROVIDER_H_