extensions: Cleanup class/struct fwd declarations

extensions/browser/api/web_request/web_request_api_helpers.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.
 
 // Helper classes and functions used for the WebRequest API.
 
 #ifndef EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_API_HELPERS_H_
 #define EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_API_HELPERS_H_
 
 #include <list>
 #include <memory>
 #include <set>
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "content/public/common/resource_type.h"
 #include "extensions/browser/warning_set.h"
 #include "net/base/auth.h"
 #include "net/http/http_request_headers.h"
 #include "net/http/http_response_headers.h"
 #include "url/gurl.h"
 
 namespace base {
 class ListValue;
-class Value;
 class DictionaryValue;
 }
 
-namespace content {
-class RenderProcessHost;
-}
-
 namespace extensions {
 class Extension;
 }
 
 namespace net {
 class NetLogWithSource;
-class URLRequest;
 }
 
 namespace extension_web_request_api_helpers {
 
 typedef std::pair<std::string, std::string> ResponseHeader;
 typedef std::vector<ResponseHeader> ResponseHeaders;
 
 // Internal representation of the extraInfoSpec parameter on webRequest
 // events, used to specify extra information to be included with network
 // events.
@@ skipping 292 matching lines @@
 
 // Stores a |content::ResourceType| representation in |types| if |type_str| is
 // a resource type handled by the web request API. Returns true in case of
 // success.
 bool ParseResourceType(const std::string& type_str,
                        std::vector<content::ResourceType>* types);
 
 }  // namespace extension_web_request_api_helpers
 
 #endif  // EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_API_HELPERS_H_