[mojo] Implement pipe fusion API

mojo/edk/system/node_controller.h

 // Copyright 2016 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_EDK_SYSTEM_NODE_CONTROLLER_H_
 #define MOJO_EDK_SYSTEM_NODE_CONTROLLER_H_
 
 #include <queue>
 #include <unordered_map>
 #include <unordered_set>
@@ skipping 72 matching lines @@
                   scoped_ptr<PortsMessage>* message);
 
   // Reserves a local port |port| associated with |token|. A peer holding a copy
   // of |token| can merge one of its own ports into this one.
   void ReservePort(const std::string& token, const ports::PortRef& port);
 
   // Merges a local port |port| into a port reserved by |token| in the parent.
   void MergePortIntoParent(const std::string& token,
                            const ports::PortRef& port);
 
+  // Merges two local ports together.
+  int MergeLocalPorts(const ports::PortRef& port0, const ports::PortRef& port1);
+
   // Creates a new shared buffer for use in the current process.
   scoped_refptr<PlatformSharedBuffer> CreateSharedBuffer(size_t num_bytes);
 
   // Request that the Node be shut down cleanly. This may take an arbitrarily
   // long time to complete, at which point |callback| will be called.
   //
   // Note that while it is safe to continue using the NodeController's public
   // interface after requesting shutdown, you do so at your own risk and there
   // is NO guarantee that new messages will be sent or ports will complete
   // transfer.
@@ skipping 152 matching lines @@
   scoped_ptr<Broker> broker_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(NodeController);
 };
 
 }  // namespace edk
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_NODE_CONTROLLER_H_