isolates refactor: this change introduces 'dart:isolate' as a library. This is a

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";
 const char* DartUtils::kJsonLibURL = "dart:json";
 const char* DartUtils::kUriLibURL = "dart:uri";
 const char* DartUtils::kUtf8LibURL = "dart:utf8";
+const char* DartUtils::kIsolateLibURL = "dart:isolate";
 
 
 const char* DartUtils::kIdFieldName = "_id";
 
 
 static const char* MapLibraryUrl(CommandLineOptions* url_mapping,
                                  const char* url_string) {
   ASSERT(url_mapping != NULL);
   // We need to check if the passed in url is found in the url_mapping array,
   // in that case use the mapped entry.
@@ skipping 231 matching lines @@
 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);
 }