Provide a Mojo equivalent of ThreadSafeSender.

ipc/ipc_channel_proxy.cc

 // 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.
 
 #include "ipc/ipc_channel_proxy.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <utility>
@@ skipping 293 matching lines @@
     if (filters_[i].get() == filter) {
       filter->OnFilterRemoved();
       filters_.erase(filters_.begin() + i);
       return;
     }
   }
 
   NOTREACHED() << "filter to be removed not found";
 }
 
+void ChannelProxy::Context::RunWithChannel(
+    const RunOnIOThreadCallback& callback) {
+  callback.Run(channel_.get());
+}
+
 // Called on the listener's thread
 void ChannelProxy::Context::AddFilter(MessageFilter* filter) {
   base::AutoLock auto_lock(pending_filters_lock_);
   pending_filters_.push_back(make_scoped_refptr(filter));
   ipc_task_runner_->PostTask(
       FROM_HERE, base::Bind(&Context::OnAddFilter, this));
 }
 
 // Called on the listener's thread
 void ChannelProxy::Context::OnDispatchMessage(const Message& message) {
@@ skipping 279 matching lines @@
 
 void ChannelProxy::GetGenericRemoteAssociatedInterface(
     const std::string& name,
     mojo::ScopedInterfaceEndpointHandle handle) {
   DCHECK(did_init_);
   context_->ipc_task_runner()->PostTask(
       FROM_HERE, base::Bind(&Context::GetRemoteAssociatedInterface,
                             context_, name, base::Passed(&handle)));
 }
 
+void ChannelProxy::RunOnIOThread(const RunOnIOThreadCallback& callback) {
+  DCHECK(did_init_);
+  context_->ipc_task_runner()->PostTask(
+      FROM_HERE, base::Bind(&Context::RunWithChannel, context_, callback));
+}
+
 void ChannelProxy::ClearIPCTaskRunner() {
   DCHECK(CalledOnValidThread());
 
   context()->ClearIPCTaskRunner();
 }
 
 void ChannelProxy::OnChannelInit() {
 }
 
 //-----------------------------------------------------------------------------
 
 }  // namespace IPC