[mojo-edk] Simplify multiprocess pipe bootstrap

mojo/edk/system/remote_message_pipe_bootstrap.cc

Index: mojo/edk/system/remote_message_pipe_bootstrap.cc
diff --git a/mojo/edk/system/remote_message_pipe_bootstrap.cc b/mojo/edk/system/remote_message_pipe_bootstrap.cc
index 671542f3595c72615a74b18919d0bcd9dbd181bc..234216633f2fc074d39e29681fd4dec44f592cc1 100644
--- a/mojo/edk/system/remote_message_pipe_bootstrap.cc
+++ b/mojo/edk/system/remote_message_pipe_bootstrap.cc
@@ -31,18 +31,17 @@ struct BootstrapData {
 void RemoteMessagePipeBootstrap::Create(
     NodeController* node_controller,
     ScopedPlatformHandle platform_handle,
-    const ports::PortRef& port,
-    const base::Closure& callback) {
+    const ports::PortRef& port) {
   if (node_controller->io_task_runner()->RunsTasksOnCurrentThread()) {
     // Owns itself.
-    new RemoteMessagePipeBootstrap(node_controller, std::move(platform_handle),
-                                   port, callback);
+    new RemoteMessagePipeBootstrap(
+        node_controller, std::move(platform_handle), port);
   } else {
     node_controller->io_task_runner()->PostTask(
         FROM_HERE,
         base::Bind(&RemoteMessagePipeBootstrap::Create,
                    base::Unretained(node_controller),
-                   base::Passed(&platform_handle), port, callback));
+                   base::Passed(&platform_handle), port));
   }
 }
 
@@ -56,11 +55,9 @@ RemoteMessagePipeBootstrap::~RemoteMessagePipeBootstrap() {
 RemoteMessagePipeBootstrap::RemoteMessagePipeBootstrap(
     NodeController* node_controller,
     ScopedPlatformHandle platform_handle,
-    const ports::PortRef& port,
-    const base::Closure& callback)
+    const ports::PortRef& port)
     : node_controller_(node_controller),
       local_port_(port),
-      callback_(callback),
       io_task_runner_(base::ThreadTaskRunnerHandle::Get()),
       channel_(Channel::Create(this, std::move(platform_handle),
                                io_task_runner_)) {
@@ -119,8 +116,14 @@ void RemoteMessagePipeBootstrap::OnChannelMessage(
   }
 
   peer_info_received_ = true;
-  node_controller_->ConnectToRemotePort(
-      local_port_, data->node_name, data->port_name, callback_);
+
+  // We need to choose one side to initiate the port merge. It doesn't matter
+  // who does it as long as they don't both try. Simple solution: pick the one
+  // with the "smaller" port name.
+  if (local_port_.name() < data->port_name) {
+    node_controller_->node()->MergePorts(local_port_, data->node_name,
+                                         data->port_name);
+  }
 
   // Send another ping to the other end to trigger shutdown. This may race with
   // the other end sending its own ping, but it doesn't matter. Whoever wins