Convert ValidationMessageBubbleView to BubbleDialogDelegate

chrome/browser/ui/tab_dialogs.h

 // Copyright 2014 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_TAB_DIALOGS_H_
 #define CHROME_BROWSER_UI_TAB_DIALOGS_H_
 
 #include <memory>
 #include <string>
 
+#include "base/memory/weak_ptr.h"
 #include "base/strings/string16.h"
 #include "base/supports_user_data.h"
 #include "chrome/browser/ui/validation_message_bubble.h"
 #include "ui/gfx/native_widget_types.h"
 
 class Browser;
 class Profile;
 
 namespace content {
 class WebContents;
@@ skipping 35 matching lines @@
       Browser* browser,
       Profile* profile,
       const std::string& username,
       ui::ProfileSigninConfirmationDelegate* delegate) = 0;
 
   // Shows or hides the ManagePasswords bubble.
   // Pass true for |user_action| if this is a user initiated action.
   virtual void ShowManagePasswordsBubble(bool user_action) = 0;
   virtual void HideManagePasswordsBubble() = 0;
 
-  virtual std::unique_ptr<ValidationMessageBubble> ShowValidationMessage(
+  virtual base::WeakPtr<ValidationMessageBubble> ShowValidationMessage(
       const gfx::Rect& anchor_in_root_view,
       const base::string16& main_text,
       const base::string16& sub_text) = 0;
 
  protected:
   static const void* UserDataKey();
 };
 
 #endif  // CHROME_BROWSER_UI_TAB_DIALOGS_H_