[UI Views] Don't allow a ButtonListener and a MenuButtonListener

chrome/browser/ui/views/website_settings/permissions_bubble_view.cc

 // 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.
 
 #include "chrome/browser/ui/views/website_settings/permissions_bubble_view.h"
 
 #include <stddef.h>
 
 #include "base/macros.h"
 #include "base/strings/string16.h"
@@ skipping 83 matching lines @@
   int index_;
   Listener* listener_;
   scoped_ptr<PermissionMenuModel> model_;
   scoped_ptr<views::MenuRunner> menu_runner_;
 };
 
 PermissionCombobox::PermissionCombobox(Listener* listener,
                                        int index,
                                        const GURL& url,
                                        ContentSetting setting)
-    : MenuButton(nullptr, base::string16(), this, true),
+    : MenuButton(base::string16(), this, true),
       index_(index),
       listener_(listener),
       model_(new PermissionMenuModel(
           url,
           setting,
           base::Bind(&PermissionCombobox::PermissionChanged,
                      base::Unretained(this)))) {
   SetText(model_->GetLabelAt(model_->GetIndexOfCommandId(setting)));
   SizeToPreferredSize();
 }
@@ skipping 381 matching lines @@
 
 void PermissionBubbleViewViews::Accept() {
   if (delegate_)
     delegate_->Accept();
 }
 
 void PermissionBubbleViewViews::Deny() {
   if (delegate_)
     delegate_->Deny();
 }