Mojo: Add Channel::AttachEndpoint(), which takes a ChannelEndpoint.

mojo/system/channel.h

 // Copyright 2013 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.
 
 #ifndef MOJO_SYSTEM_CHANNEL_H_
 #define MOJO_SYSTEM_CHANNEL_H_
 
 #include <stdint.h>
 
 #include "base/compiler_specific.h"
@@ skipping 13 matching lines @@
 #include "mojo/system/system_impl_export.h"
 
 namespace mojo {
 
 namespace embedder {
 class PlatformSupport;
 }
 
 namespace system {
 
+class ChannelEndpoint;
+
 // This class is mostly thread-safe. It must be created on an I/O thread.
 // |Init()| must be called on that same thread before it becomes thread-safe (in
 // particular, before references are given to any other thread) and |Shutdown()|
 // must be called on that same thread before destruction. Its public methods are
 // otherwise thread-safe. (Many private methods are restricted to the creation
 // thread.) It may be destroyed on any thread, in the sense that the last
 // reference to it may be released on any thread, with the proviso that
 // |Shutdown()| must have been called first (so the pattern is that a "main"
 // reference is kept on its creation thread and is released after |Shutdown()|
 // is called, but other threads may have temporarily "dangling" references).
@@ skipping 31 matching lines @@
   // This must be called on the creation thread before destruction (which can
   // happen on any thread).
   void Shutdown();
 
   // Signals that |Shutdown()| will be called soon (this may be called from any
   // thread, unlike |Shutdown()|). Warnings will be issued if, e.g., messages
   // are written after this is called; other warnings may be suppressed. (This
   // may be called multiple times, or not at all.)
   void WillShutdownSoon();
 
+  // TODO(vtl): Write comment here.
+  MessageInTransit::EndpointId AttachEndpoint(
+      scoped_refptr<ChannelEndpoint> endpoint);
+
+  // TODO(vtl): Remove this version.
   // Attaches the given message pipe/port's endpoint (which must be a
   // |ProxyMessagePipeEndpoint|) to this channel. This assigns it a local ID,
   // which it returns. The first message pipe endpoint attached will always have
   // |kBootstrapEndpointId| as its local ID. (For bootstrapping, this occurs on
   // both sides, so one should use |kBootstrapEndpointId| for the remote ID for
   // the first message pipe across a channel.) Returns |kInvalidEndpointId| on
   // failure.
   // TODO(vtl): This should be combined with "run", and it should take a
   // |ChannelEndpoint| instead.
   // TODO(vtl): Maybe limit the number of attached message pipes.
@@ skipping 100 matching lines @@
   // be checked for existence before use.
   MessageInTransit::EndpointId next_local_id_;
 
   DISALLOW_COPY_AND_ASSIGN(Channel);
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_SYSTEM_CHANNEL_H_