Fix Mac build.

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "include/dart_api.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
 #include "vm/dart.h"
@@ skipping 882 matching lines @@
     OS::PrintErr("%s expects argument 'handler' to be non-null.\n",
                  CURRENT_FUNC);
     return kIllegalPort;
   }
   // Start the native port without a current isolate.
   IsolateSaver saver(Isolate::Current());
   Isolate::SetCurrent(NULL);
 
   NativeMessageHandler* nmh = new NativeMessageHandler(name, handler);
   Dart_Port port_id = PortMap::CreatePort(nmh);
-  nmh->Run(Dart::thread_pool(), NULL, NULL, NULL);
+  nmh->Run(Dart::thread_pool(), NULL, NULL, 0);
   return port_id;
 }
 
 
 DART_EXPORT bool Dart_CloseNativePort(Dart_Port native_port_id) {
   // Close the native port without a current isolate.
   IsolateSaver saver(Isolate::Current());
   Isolate::SetCurrent(NULL);
 
   // TODO(turnidge): Check that the port is native before trying to close.
@@ skipping 2408 matching lines @@
       *buffer = NULL;
     }
     delete debug_region;
   } else {
     *buffer = NULL;
     *buffer_size = 0;
   }
 }
 
 }  // namespace dart