Added API Dart_PostCMessage for posting a Dart_CMessage structure

runtime/bin/dartutils.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 "bin/dartutils.h"
 
 #include "bin/file.h"
+#include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/globals.h"
 
 const char* DartUtils::kDartScheme = "dart:";
 const char* DartUtils::kBuiltinLibURL = "dart:builtin";
 const char* DartUtils::kCoreLibURL = "dart:core";
 const char* DartUtils::kCoreImplLibURL = "dart:coreimpl";
 const char* DartUtils::kIOLibURL = "dart:io";
 
 
@@ skipping 204 matching lines @@
            path, File::PathSeparator(), filename);
 
   free(path);
   char* canonical_filename = File::GetCanonicalPath(absolute_filename);
   if (canonical_filename == NULL) {
     return absolute_filename;
   }
   free(absolute_filename);
   return canonical_filename;
 }
+
+
+bool DartUtils::PostNull(Dart_Port port_id) {
+  // Post a message with just the null object.
+  Dart_CObject object;
+  object.type = Dart_CObject::kNull;
+  return Dart_PostCObject(port_id, &object);
+}
+
+
+bool DartUtils::PostInt32(Dart_Port port_id, int32_t value) {
+  // Post a message with the integer value.
+  int32_t min = 0xc0000000;  // -1073741824
+  int32_t max = 0x3fffffff;  // 1073741823
+  ASSERT(min <= value && value < max);
+  Dart_CObject object;
+  object.type = Dart_CObject::kInt32;
+  object.value.as_int32 = value;
+  return Dart_PostCObject(port_id, &object);
+}