Use service process to collect printers.

chrome/service/service_ipc_server.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 CHROME_SERVICE_SERVICE_IPC_SERVER_H_
 #define CHROME_SERVICE_SERVICE_IPC_SERVER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 42 matching lines @@
   virtual void OnChannelError() OVERRIDE;
 
   // IPC message handlers.
   void OnEnableCloudPrintProxyWithRobot(
       const std::string& robot_auth_code,
       const std::string& robot_email,
       const std::string& user_email,
       const base::DictionaryValue& user_settings);
   void OnGetCloudPrintProxyInfo();
   void OnGetHistograms();
+  void OnGetPrinters();
   void OnDisableCloudPrintProxy();
 
   void OnShutdown();
   void OnUpdateAvailable();
 
   // Helper method to create the sync channel.
   void CreateChannel();
 
   IPC::ChannelHandle channel_handle_;
   scoped_ptr<IPC::SyncChannel> channel_;
   // Indicates whether a client is currently connected to the channel.
   bool client_connected_;
 
   // Allows threads other than the main thread to send sync messages.
   scoped_refptr<IPC::SyncMessageFilter> sync_message_filter_;
 
   // Calculates histograms deltas.
   scoped_ptr<base::HistogramDeltaSerialization> histogram_delta_serializer_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceIPCServer);
 };
 
 #endif  // CHROME_SERVICE_SERVICE_IPC_SERVER_H_