Adds a special case for sending an int over a port with the native API.

runtime/include/dart_native_api.h

 /*
  * Copyright (c) 2013, 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.
  */
 
 #ifndef INCLUDE_DART_NATIVE_API_H_
 #define INCLUDE_DART_NATIVE_API_H_
 
 #include "include/dart_api.h"
@@ skipping 84 matching lines @@
  * restored.
  *
  * \param port_id The destination port.
  * \param message The message to send.
  *
  * \return True if the message was posted.
  */
 DART_EXPORT bool Dart_PostCObject(Dart_Port port_id, Dart_CObject* message);
 
 /**
+ * Posts a message on some port. The message will contain the integer 'message'.
+ *
+ * \param port_id The destination port.
+ * \param message The message to send.
+ *
+ * \return True if the message was posted.
+ */
+DART_EXPORT bool Dart_PostInteger(Dart_Port port_id, intptr_t message);
+
+/**
  * A native message handler.
  *
  * This handler is associated with a native port by calling
  * Dart_NewNativePort.
  *
  * The message received is decoded into the message structure. The
  * lifetime of the message data is controlled by the caller. All the
  * data references from the message are allocated by the caller and
  * will be reclaimed when returning to it.
  */
@@ skipping 39 matching lines @@
 
 /**
  * Forces all loaded classes and functions to be compiled eagerly in
  * the current isolate..
  *
  * TODO(turnidge): Document.
  */
 DART_EXPORT Dart_Handle Dart_CompileAll();
 
 #endif  /* INCLUDE_DART_NATIVE_API_H_ */  /* NOLINT */