Restructure pkg/unittest and pkg/webdriver to follow the pub conventions.

tests/isolate/multiple_timer_test.dart

 // 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.
 
-#library('multiple_timer_test');
+library multiple_timer_test;
 
-#import("dart:isolate");
-#import('../../pkg/unittest/unittest.dart');
+import 'dart:isolate';
+import '../../pkg/unittest/lib/unittest.dart';
 
 const int TIMEOUT1 = 1000;
 const int TIMEOUT2 = 2000;
 const int TIMEOUT3 = 500;
 const int TIMEOUT4 = 1500;
 
 main() {
   test("multiple timer test", () {
     int _startTime1;
     int _startTime2;
@@ skipping 40 matching lines @@
     _startTime1 = (new Date.now()).millisecondsSinceEpoch;
     new Timer(TIMEOUT1, expectAsync1(timeoutHandler1));
     _startTime2 = (new Date.now()).millisecondsSinceEpoch;
     new Timer(TIMEOUT2, expectAsync1(timeoutHandler2));
     _startTime3 = (new Date.now()).millisecondsSinceEpoch;
     new Timer(TIMEOUT3, expectAsync1(timeoutHandler3));
     _startTime4 = (new Date.now()).millisecondsSinceEpoch;
     new Timer(TIMEOUT4, expectAsync1(timeoutHandler4));
   });
 }