Fix memory management of VoiceSearchBarView.

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

Index: ios/public/provider/chrome/browser/voice/voice_search_provider.h
diff --git a/ios/public/provider/chrome/browser/voice/voice_search_provider.h b/ios/public/provider/chrome/browser/voice/voice_search_provider.h
index 05be8e6253dc4371a1503d20d9c47ed0d3dfed0b..58f4ba6e867ee487f008b4f7d3913f361bbd0c92 100644
--- a/ios/public/provider/chrome/browser/voice/voice_search_provider.h
+++ b/ios/public/provider/chrome/browser/voice/voice_search_provider.h
@@ -41,9 +41,14 @@ class VoiceSearchProvider {
       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);
 };