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

chrome/browser/extensions/extension_message_bubble_controller.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_BUBBLE_CONTROLLER_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_BUBBLE_CONTROLLER_H_
 
 #include <string>
 #include "chrome/browser/extensions/extension_message_bubble.h"
 #include "extensions/browser/browser_context_keyed_api_factory.h"
@@ skipping 35 matching lines @@
     virtual base::string16 GetOverflowText(
         const base::string16& overflow_count) const = 0;
     virtual base::string16 GetLearnMoreLabel() const = 0;
     virtual GURL GetLearnMoreUrl() const = 0;
     virtual base::string16 GetActionButtonLabel() const = 0;
     virtual base::string16 GetDismissButtonLabel() const = 0;
 
     // Whether to show a list of extensions in the bubble.
     virtual bool ShouldShowExtensionList() const = 0;
 
+    // In some cases, we want the delegate only to handle a single extension
+    // and this sets which extension.
+    virtual void RestrictToSingleExtension(const std::string& extension_id);
+
     // Record, through UMA, how many extensions were found.
     virtual void LogExtensionCount(size_t count) = 0;
     virtual void LogAction(BubbleAction action) = 0;
   };
 
   ExtensionMessageBubbleController(Delegate* delegate, Profile* profile);
   virtual ~ExtensionMessageBubbleController();
 
   Delegate* delegate() const { return delegate_.get(); }
 
@@ skipping 35 matching lines @@
 
   // Whether this class has initialized.
   bool initialized_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionMessageBubbleController);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_BUBBLE_CONTROLLER_H_