Uses ProxyConfigServiceLinux in the chromoting host to configure proxy.

net/proxy/proxy_config_service_mac.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.
 
 #ifndef NET_PROXY_PROXY_CONFIG_SERVICE_MAC_H_
 #define NET_PROXY_PROXY_CONFIG_SERVICE_MAC_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "net/base/network_config_watcher_mac.h"
 #include "net/proxy/proxy_config.h"
 #include "net/proxy/proxy_config_service.h"
 
 namespace base {
 class SingleThreadTaskRunner;
 }  // namespace base
 
 namespace net {
 
-// TODO(sergeyu): This class needs to be exported because remoting code
-// creates it directly. Fix that and remove NET_EXPORT here.
-// crbug.com/125104
-class NET_EXPORT ProxyConfigServiceMac : public ProxyConfigService {
+class ProxyConfigServiceMac : public ProxyConfigService {
  public:
   // Constructs a ProxyConfigService that watches the Mac OS system settings.
   // This instance is expected to be operated and deleted on the same thread
   // (however it may be constructed from a different thread).
   explicit ProxyConfigServiceMac(
       const scoped_refptr<base::SingleThreadTaskRunner>& io_thread_task_runner);
   virtual ~ProxyConfigServiceMac();
 
  public:
   // ProxyConfigService implementation:
@@ skipping 42 matching lines @@
 
   // The thread that we expect to be operated on.
   const scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(ProxyConfigServiceMac);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_PROXY_CONFIG_SERVICE_MAC_H_