sync: Remove unused private fields

sync/internal_api/public/http_bridge.h

 // Copyright 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.
 
 #ifndef SYNC_INTERNAL_API_PUBLIC_HTTP_BRIDGE_H_
 #define SYNC_INTERNAL_API_PUBLIC_HTTP_BRIDGE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 53 matching lines @@
     RequestContext(
         net::URLRequestContext* baseline_context,
         const scoped_refptr<base::SingleThreadTaskRunner>&
             network_task_runner,
         const std::string& user_agent);
 
     // The destructor MUST be called on the IO thread.
     ~RequestContext() override;
 
    private:
-    net::URLRequestContext* const baseline_context_;
     const scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
     scoped_ptr<net::HttpUserAgentSettings> http_user_agent_settings_;
     scoped_ptr<net::URLRequestJobFactory> job_factory_;
 
     DISALLOW_COPY_AND_ASSIGN(RequestContext);
   };
 
   // Lazy-getter for RequestContext objects.
   class SYNC_EXPORT_PRIVATE RequestContextGetter
       : public net::URLRequestContextGetter {
@@ skipping 190 matching lines @@
   NetworkTimeUpdateCallback network_time_update_callback_;
 
   CancelationSignal* const cancelation_signal_;
 
   DISALLOW_COPY_AND_ASSIGN(HttpBridgeFactory);
 };
 
 }  //  namespace syncer
 
 #endif  // SYNC_INTERNAL_API_PUBLIC_HTTP_BRIDGE_H_