Mojo: Make Channel take a RawChannel rather than creating it.

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/basictypes.h"
@@ skipping 41 matching lines @@
     : public base::RefCountedThreadSafe<Channel>,
       public RawChannel::Delegate {
  public:
   // The first message pipe endpoint attached will have this as its local ID.
   static const MessageInTransit::EndpointId kBootstrapEndpointId = 1;
 
   Channel();
 
   // This must be called on the creation thread before any other methods are
   // called, and before references to this object are given to any other
-  // threads. |handle| should be a handle to a (platform-appropriate)
-  // bidirectional communication channel (e.g., a socket on POSIX, a named pipe
-  // on Windows). Returns true on success. On failure, no other methods should
-  // be called (including |Shutdown()|).
-  bool Init(embedder::ScopedPlatformHandle handle);
+  // threads. |raw_channel| should be uninitialized. Returns true on success. On
+  // failure, no other methods should be called (including |Shutdown()|).
+  bool Init(scoped_ptr<RawChannel> raw_channel);
 
   // This must be called on the creation thread before destruction (which can
   // happen on any thread).
   void Shutdown();
 
   // 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
@@ skipping 71 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_