chrome: Cleanup class/struct forward declarations

chrome/browser/search/instant_service.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_H_
 #define CHROME_BROWSER_SEARCH_INSTANT_SERVICE_H_
 
 #include <memory>
 #include <set>
 #include <vector>
@@ skipping 11 matching lines @@
 #include "url/gurl.h"
 
 class InstantIOContext;
 struct InstantMostVisitedItem;
 class InstantSearchPrerenderer;
 class InstantServiceObserver;
 class Profile;
 struct TemplateURLData;
 class TemplateURLService;
 struct ThemeBackgroundInfo;
-class ThemeService;
 
 namespace content {
 class RenderProcessHost;
 }
 
 // Tracks render process host IDs that are associated with Instant.
 class InstantService : public KeyedService,
                        public content::NotificationObserver,
                        public TemplateURLServiceObserver,
                        public history::TopSitesObserver {
@@ skipping 126 matching lines @@
   std::unique_ptr<TemplateURLData> previous_default_search_provider_;
   GURL previous_google_base_url_;
 
   // Used for Top Sites async retrieval.
   base::WeakPtrFactory<InstantService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(InstantService);
 };
 
 #endif  // CHROME_BROWSER_SEARCH_INSTANT_SERVICE_H_