content: Cleanup class/struct forward declarations

content/public/browser/appcache_service.h

 // Copyright (c) 2012 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 CONTENT_PUBLIC_BROWSER_APPCACHE_SERVICE_H_
 #define CONTENT_PUBLIC_BROWSER_APPCACHE_SERVICE_H_
 
 #include <map>
 #include <memory>
 #include <set>
 
 #include "base/memory/ref_counted.h"
 #include "content/common/content_export.h"
 #include "content/public/common/appcache_info.h"
 #include "net/base/completion_callback.h"
 
 namespace content {
 
-class AppCacheStorage;
-
 // Refcounted container to avoid copying the collection in callbacks.
 struct CONTENT_EXPORT AppCacheInfoCollection
     : public base::RefCountedThreadSafe<AppCacheInfoCollection> {
   AppCacheInfoCollection();
 
   std::map<GURL, AppCacheInfoVector> infos_by_origin;
 
  private:
   friend class base::RefCountedThreadSafe<AppCacheInfoCollection>;
   virtual ~AppCacheInfoCollection();
@@ skipping 18 matching lines @@
   virtual void DeleteAppCacheGroup(const GURL& manifest_url,
                                    const net::CompletionCallback& callback) = 0;
 
  protected:
   virtual ~AppCacheService() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_APPCACHE_SERVICE_H_