Mojo: Implement plumbing to support passing handles over MessagePipes.

mojo/system/message_pipe_dispatcher.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_MESSAGE_PIPE_DISPATCHER_H_
 #define MOJO_SYSTEM_MESSAGE_PIPE_DISPATCHER_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
@@ skipping 15 matching lines @@
   void Init(scoped_refptr<MessagePipe> message_pipe, unsigned port);
 
  private:
   friend class base::RefCountedThreadSafe<MessagePipeDispatcher>;
   virtual ~MessagePipeDispatcher();
 
   // |Dispatcher| implementation/overrides:
   virtual void CancelAllWaitersNoLock() OVERRIDE;
   virtual MojoResult CloseImplNoLock() OVERRIDE;
   virtual MojoResult WriteMessageImplNoLock(
-      const void* bytes,
-      uint32_t num_bytes,
-      const MojoHandle* handles,
-      uint32_t num_handles,
+      const void* bytes, uint32_t num_bytes,
+      const std::vector<Dispatcher*>* dispatchers,
       MojoWriteMessageFlags flags) OVERRIDE;
   virtual MojoResult ReadMessageImplNoLock(
-      void* bytes,
-      uint32_t* num_bytes,
-      MojoHandle* handles,
-      uint32_t* num_handles,
+      void* bytes, uint32_t* num_bytes,
+      uint32_t max_num_dispatchers,
+      std::vector<scoped_refptr<Dispatcher> >* dispatchers,
       MojoReadMessageFlags flags) OVERRIDE;
   virtual MojoResult AddWaiterImplNoLock(Waiter* waiter,
                                          MojoWaitFlags flags,
                                          MojoResult wake_result) OVERRIDE;
   virtual void RemoveWaiterImplNoLock(Waiter* waiter) OVERRIDE;
 
   // Protected by |lock()|:
   scoped_refptr<MessagePipe> message_pipe_;  // This will be null if closed.
   unsigned port_;
 
   DISALLOW_COPY_AND_ASSIGN(MessagePipeDispatcher);
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_SYSTEM_MESSAGE_PIPE_DISPATCHER_H_