Remove forward-declaration of non-existent class

components/google/core/browser/google_url_tracker.h

 // 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.
 
 #ifndef COMPONENTS_GOOGLE_CORE_BROWSER_GOOGLE_URL_TRACKER_H_
 #define COMPONENTS_GOOGLE_CORE_BROWSER_GOOGLE_URL_TRACKER_H_
 
 #include "base/callback_forward.h"
 #include "base/callback_list.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "components/google/core/browser/google_url_tracker_client.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "net/base/network_change_notifier.h"
 #include "net/url_request/url_fetcher.h"
 #include "net/url_request/url_fetcher_delegate.h"
 #include "url/gurl.h"
 
-class GoogleURLTrackerNavigationHelper;
 class PrefService;
 
 namespace infobars {
 class InfoBar;
 }
 
 // This object is responsible for checking the Google URL once per network
 // change.  The current value is saved to prefs.
 //
 // Most consumers should only call google_url().  Consumers who need to be
@@ skipping 85 matching lines @@
                            // updated URL.  If this is never set, we won't
                            // bother to fetch anything.
                            // Consumers should register a callback via
                            // RegisterCallback().
   base::WeakPtrFactory<GoogleURLTracker> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(GoogleURLTracker);
 };
 
 #endif  // COMPONENTS_GOOGLE_CORE_BROWSER_GOOGLE_URL_TRACKER_H_