Settings Overides -- warn user when extensions override their NTP.

chrome/browser/extensions/extension_message_bubble_controller.cc

 // Copyright (c) 2013 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/extensions/extension_message_bubble_controller.h"
 
 #include "base/bind.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/extensions/extension_message_bubble.h"
@@ skipping 11 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 // ExtensionMessageBubbleController::Delegate
 
 ExtensionMessageBubbleController::Delegate::Delegate() {
 }
 
 ExtensionMessageBubbleController::Delegate::~Delegate() {
 }
 
+void ExtensionMessageBubbleController::Delegate::RestrictToSingleExtension(
+    const std::string& extension_id) {
+  NOTIMPLEMENTED();  // Derived classes that need this should implement.
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // ExtensionMessageBubbleController
 
 ExtensionMessageBubbleController::ExtensionMessageBubbleController(
     Delegate* delegate, Profile* profile)
     : profile_(profile),
       user_action_(ACTION_BOUNDARY),
       delegate_(delegate),
       initialized_(false) {
 }
@@ skipping 113 matching lines @@
     }
 
     delegate_->LogExtensionCount(extension_list_.size());
     initialized_ = true;
   }
 
   return &extension_list_;
 }
 
 }  // namespace extensions