chrome: Cleanup class/struct forward declarations

chrome/browser/supervised_user/experimental/safe_search_url_reporter.h

 // Copyright 2016 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 CHROME_BROWSER_SUPERVISED_USER_EXPERIMENTAL_SAFE_SEARCH_URL_REPORTER_H_
 #define CHROME_BROWSER_SUPERVISED_USER_EXPERIMENTAL_SAFE_SEARCH_URL_REPORTER_H_
 
 #include <memory>
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "google_apis/gaia/oauth2_token_service.h"
 #include "net/url_request/url_fetcher_delegate.h"
 #include "url/gurl.h"
 
 class GURL;
 class Profile;
 
 namespace net {
 class URLFetcher;
-class URLReportContextGetter;
 }
 
 class SafeSearchURLReporter : public OAuth2TokenService::Consumer,
                               public net::URLFetcherDelegate {
  public:
   using SuccessCallback = base::Callback<void(bool)>;
   
   SafeSearchURLReporter(OAuth2TokenService* oauth2_token_service,
                         const std::string& account_id,
                         net::URLRequestContextGetter* context);
@@ skipping 30 matching lines @@
   std::string account_id_;
   net::URLRequestContextGetter* context_;
   int url_fetcher_id_;
 
   std::vector<std::unique_ptr<Report>> reports_;
 
   DISALLOW_COPY_AND_ASSIGN(SafeSearchURLReporter);
 };
 
 #endif  // CHROME_BROWSER_SUPERVISED_USER_EXPERIMENTAL_SAFE_SEARCH_URL_REPORTER_H_