ChannelProxy: Send() from UI thread when ChannelMojo is used.

ipc/ipc_channel_proxy.cc

Index: ipc/ipc_channel_proxy.cc
diff --git a/ipc/ipc_channel_proxy.cc b/ipc/ipc_channel_proxy.cc
index 64fab8fca56db0067e909aa5f96d2fe04443e912..88e3f051c71d161998bf4af5e224ff461eae10b6 100644
--- a/ipc/ipc_channel_proxy.cc
+++ b/ipc/ipc_channel_proxy.cc
@@ -30,6 +30,7 @@ ChannelProxy::Context::Context(
       ipc_task_runner_(ipc_task_runner),
       channel_connected_called_(false),
       message_filter_router_(new MessageFilterRouter()),
+      channel_send_thread_safe_(false),
       peer_pid_(base::kNullProcessId) {
   DCHECK(ipc_task_runner_.get());
   // The Listener thread where Messages are handled must be a separate thread
@@ -54,6 +55,7 @@ void ChannelProxy::Context::CreateChannel(scoped_ptr<ChannelFactory> factory) {
   DCHECK(!channel_);
   channel_id_ = factory->GetName();
   channel_ = factory->BuildChannel(this);
+  channel_send_thread_safe_ = channel_->IsSendThreadSafe();
 }
 
 bool ChannelProxy::Context::TryFilters(const Message& message) {
@@ -155,7 +157,7 @@ void ChannelProxy::Context::OnChannelClosed() {
   // access it any more.
   pending_filters_.clear();
 
-  channel_.reset();
+  ClearChannel();
 
   // Balance with the reference taken during startup.  This may result in
   // self-destruction.
@@ -303,6 +305,30 @@ void ChannelProxy::Context::OnDispatchBadMessage(const Message& message) {
     listener_->OnBadMessageReceived(message);
 }
 
+void ChannelProxy::Context::ClearChannel() {
+  base::AutoLock l(channel_lifetime_lock_);
+  channel_.reset();
+}
+
+void ChannelProxy::Context::SendFromThisThread(Message* message) {
+  base::AutoLock l(channel_lifetime_lock_);
+  if (!channel_)
+    return;
+  DCHECK(channel_->IsSendThreadSafe());
+  channel_->Send(message);
+}
+
+void ChannelProxy::Context::Send(Message* message) {
+  if (channel_send_thread_safe_) {
+    SendFromThisThread(message);
+    return;
+  }
+
+  ipc_task_runner()->PostTask(
+      FROM_HERE, base::Bind(&ChannelProxy::Context::OnSendMessage, this,
+                            base::Passed(scoped_ptr<Message>(message))));
+}
+
 //-----------------------------------------------------------------------------
 
 // static
@@ -407,10 +433,7 @@ bool ChannelProxy::Send(Message* message) {
   Logging::GetInstance()->OnSendMessage(message, context_->channel_id());
 #endif
 
-  context_->ipc_task_runner()->PostTask(
-      FROM_HERE,
-      base::Bind(&ChannelProxy::Context::OnSendMessage,
-                 context_, base::Passed(scoped_ptr<Message>(message))));
+  context_->Send(message);
   return true;
 }