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

tests/isolate/src/IsolateComplexMessagesTest.dart

 // Copyright (c) 2011, 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.
 
 // Dart test program for testing isolate communication with
 // complex messages.
 
-#library("IsolateComplexMessagesTest");
-#import("TestFramework.dart");
+#library('IsolateComplexMessagesTest');
+#import('dart:isolate');
+#import('TestFramework.dart');
 
 
 void test(TestExpectation expect) {
   expect.completes(new LogIsolate().spawn()).then((SendPort remote) {
 
     remote.send(1, null);
     remote.send("Hello", null);
     remote.send("World", null);
     remote.send(const [null, 1, 2, 3, 4], null);
     remote.send(const [1, 2.0, true, false, 0xffffffffff], null);
@@ skipping 53 matching lines @@
         }
         count++;
       }
     });
   }
 }
 
 main() {
   runTests([test]);
 }