Reload Instant NTP and Instant-process tabs on search url change

chrome/browser/search/instant_service_observer.h

 // Copyright 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_SEARCH_INSTANT_SERVICE_OBSERVER_H_
 #define CHROME_BROWSER_SEARCH_INSTANT_SERVICE_OBSERVER_H_
 
 #include <vector>
 
 struct InstantMostVisitedItem;
 struct ThemeBackgroundInfo;
 
 // InstantServiceObserver defines the observer interface for InstantService.
 class InstantServiceObserver {
  public:
   // Indicates that the user's custom theme has changed in some way.
-  virtual void ThemeInfoChanged(const ThemeBackgroundInfo&) = 0;
+  virtual void ThemeInfoChanged(const ThemeBackgroundInfo&);
 
   // Indicates that the most visited items has changed.
   virtual void MostVisitedItemsChanged(
-      const std::vector<InstantMostVisitedItem>&) = 0;
+      const std::vector<InstantMostVisitedItem>&);
+
+  // Indicates that the search provider setting was changed.
+  virtual void DefaultSearchProviderChanged();
+
+  // Indicates that the Google URL has changed as a result of searchdomaincheck.
+  virtual void GoogleURLUpdated();
 
  protected:
   virtual ~InstantServiceObserver() {}
 };
 
 #endif  // CHROME_BROWSER_SEARCH_INSTANT_SERVICE_OBSERVER_H_