chrome: Cleanup class/struct forward declarations

chrome/browser/devtools/devtools_network_conditions.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 CHROME_BROWSER_DEVTOOLS_DEVTOOLS_NETWORK_CONDITIONS_H_
 #define CHROME_BROWSER_DEVTOOLS_DEVTOOLS_NETWORK_CONDITIONS_H_
 
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
 
-class GURL;
-
 // DevToolsNetworkConditions holds information about desired network conditions.
 class DevToolsNetworkConditions {
  public:
   DevToolsNetworkConditions();
   ~DevToolsNetworkConditions();
 
   explicit DevToolsNetworkConditions(bool offline);
   DevToolsNetworkConditions(bool offline,
                             double latency,
                             double download_throughput,
                             double upload_throughput);
 
   bool IsThrottling() const;
 
   bool offline() const { return offline_; }
   double latency() const { return latency_; }
   double download_throughput() const { return download_throughput_; }
   double upload_throughput() const { return upload_throughput_; }
 
  private:
   const bool offline_;
   const double latency_;
   const double download_throughput_;
   const double upload_throughput_;
 
   DISALLOW_COPY_AND_ASSIGN(DevToolsNetworkConditions);
 };
 
 #endif  // CHROME_BROWSER_DEVTOOLS_DEVTOOLS_NETWORK_CONDITIONS_H_