Revert of Clean up public interface of AttachmentBrokerUnprivileged.

remoting/host/remoting_me2me_host.cc

Index: remoting/host/remoting_me2me_host.cc
diff --git a/remoting/host/remoting_me2me_host.cc b/remoting/host/remoting_me2me_host.cc
index 03263e7ffd26c36e7a48eb6e86e4a4c461000d86..589c24b29e6b62132ed507ff98ac7f79641f0167 100644
--- a/remoting/host/remoting_me2me_host.cc
+++ b/remoting/host/remoting_me2me_host.cc
@@ -458,6 +458,9 @@
   // Accessed on the UI thread.
   scoped_ptr<IPC::ChannelProxy> daemon_channel_;
 
+  // AttachmentBroker for |daemon_channel_|.
+  scoped_ptr<IPC::AttachmentBrokerUnprivileged> attachment_broker_;
+
   // Owned as |desktop_environment_factory_|.
   DesktopSessionConnector* desktop_session_connector_ = nullptr;
 #endif  // defined(REMOTING_MULTI_PROCESS)
@@ -539,10 +542,11 @@
                                               this,
                                               context_->network_task_runner());
 
-  IPC::AttachmentBrokerUnprivileged::CreateBrokerIfNeeded();
-  IPC::AttachmentBroker* broker = IPC::AttachmentBroker::GetGlobal();
-  if (broker && !broker->IsPrivilegedBroker())
-    broker->DesignateBrokerCommunicationChannel(daemon_channel_.get());
+  attachment_broker_ = IPC::AttachmentBrokerUnprivileged::CreateBroker();
+  if (attachment_broker_) {
+    attachment_broker_->DesignateBrokerCommunicationChannel(
+        daemon_channel_.get());
+  }
 
 #else  // !defined(REMOTING_MULTI_PROCESS)
   if (cmd_line->HasSwitch(kHostConfigSwitchName)) {