content: Cleanup class/struct forward declarations

chromecast/browser/cast_content_browser_client.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 CHROMECAST_BROWSER_CAST_CONTENT_BROWSER_CLIENT_H_
 #define CHROMECAST_BROWSER_CAST_CONTENT_BROWSER_CLIENT_H_
 
 #include <map>
 #include <memory>
 #include <string>
@@ skipping 11 matching lines @@
 }
 
 namespace media {
 class BrowserCdmFactory;
 }
 
 namespace metrics {
 class MetricsService;
 }
 
+namespace net {
+class URLRequestContextGetter;
+class X509Certificate;
+}
+
 namespace service_manager {
 class InterfaceRegistry;
 }
 
 namespace chromecast {
 class CastService;
 
 namespace media {
 class MediaCapsImpl;
 class MediaPipelineBackend;
@@ skipping 162 matching lines @@
   CastBrowserMainParts* cast_browser_main_parts_;
   std::unique_ptr<URLRequestContextFactory> url_request_context_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CastContentBrowserClient);
 };
 
 }  // namespace shell
 }  // namespace chromecast
 
 #endif  // CHROMECAST_BROWSER_CAST_CONTENT_BROWSER_CLIENT_H_