blimp: Cleanup class/struct forward declarations

blimp/engine/app/blimp_url_request_context_getter.h

 // Copyright 2015 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 BLIMP_ENGINE_APP_BLIMP_URL_REQUEST_CONTEXT_GETTER_H_
 #define BLIMP_ENGINE_APP_BLIMP_URL_REQUEST_CONTEXT_GETTER_H_
 
 #include <memory>
 
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/content_browser_client.h"
 #include "net/url_request/url_request_context_getter.h"
 
 namespace base {
-class MessageLoop;
 class SingleThreadTaskRunner;
 }
 
 namespace net {
 class HostResolver;
-class NetworkDelegate;
 class NetLog;
 class ProxyConfigService;
-class ProxyService;
 }
 
 namespace blimp {
 namespace engine {
 
 // The URLRequestContextGetter for Blimp "user" requests.
 // System request context is handled in a separate class.
 class BlimpURLRequestContextGetter : public net::URLRequestContextGetter {
  public:
   // The content of |protocol_handlers| is is swapped into the new instance.
@@ skipping 27 matching lines @@
   content::ProtocolHandlerMap protocol_handlers_;
   content::URLRequestInterceptorScopedVector request_interceptors_;
 
   DISALLOW_COPY_AND_ASSIGN(BlimpURLRequestContextGetter);
 };
 
 }  // namespace engine
 }  // namespace blimp
 
 #endif  // BLIMP_ENGINE_APP_BLIMP_URL_REQUEST_CONTEXT_GETTER_H_