Adding synthetic field trial for DataReductionProxyEnabled

chrome/browser/net/spdyproxy/data_reduction_proxy_chrome_settings.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_NET_SPDYPROXY_DATA_REDUCTION_PROXY_CHROME_SETTINGS_H_
 #define CHROME_BROWSER_NET_SPDYPROXY_DATA_REDUCTION_PROXY_CHROME_SETTINGS_H_
 
 #include "components/data_reduction_proxy/browser/data_reduction_proxy_settings.h"
 #include "components/keyed_service/core/keyed_service.h"
 
@@ skipping 15 matching lines @@
       data_reduction_proxy::DataReductionProxyParams* params);
 
   // Destructs the settings object.
   virtual ~DataReductionProxyChromeSettings();
 
   // Initialize the settings object with the given profile, which it uses to
   // get the appropriate pref service.
   virtual void InitDataReductionProxySettings(Profile* profile);
 
  private:
+  // Registers the DataReductionProxyEnabled synthetic field trial with
+  // the group |data_reduction_proxy_enabled|.
+  void RegisterSyntheticFieldTrial(bool data_reduction_proxy_enabled);
+
   DISALLOW_COPY_AND_ASSIGN(DataReductionProxyChromeSettings);
 };
 
 #endif  // CHROME_BROWSER_NET_SPDYPROXY_DATA_REDUCTION_PROXY_CHROME_SETTINGS_H_