Remoting: Remove references to POSIX shared memory.

ipc/attachment_broker_privileged.h

Index: ipc/attachment_broker_privileged.h
diff --git a/ipc/attachment_broker_privileged.h b/ipc/attachment_broker_privileged.h
index 023927a092af3b09b8bef9b9285a366acf885884..8a4a93db931845417aa1ea0767ecbd47e2d48709 100644
--- a/ipc/attachment_broker_privileged.h
+++ b/ipc/attachment_broker_privileged.h
@@ -40,6 +40,11 @@ class IPC_EXPORT AttachmentBrokerPrivileged : public IPC::AttachmentBroker {
   static void CreateBrokerIfNeeded();
 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 
+  // Similar to CreateBrokerIfNeeded(), but useful for single process unit tests
+  // that don't need real attachment brokering, and don't want to deal with
+  // setting up a fake PortProvider.
+  static void CreateBrokerForSingleProcessTests();
+
   // AttachmentBroker overrides.
   void RegisterCommunicationChannel(Endpoint* endpoint) override;
   void DeregisterCommunicationChannel(Endpoint* endpoint) override;