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

tests/html/typed_arrays_5_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('typed_arrays_5_test');
-#import('../../pkg/unittest/unittest.dart');
-#import('../../pkg/unittest/html_config.dart');
-#import('dart:html');
+library typed_arrays_5_test;
+import '../../pkg/unittest/lib/unittest.dart';
+import '../../pkg/unittest/lib/html_config.dart';
+import 'dart:html';
 
 main() {
   useHtmlConfiguration();
 
   test('filter_dynamic', () {
       var a = new Float32Array(1024);
       for (int i = 0; i < a.length; i++) {
         a[i] = i;
       }
 
@@ skipping 16 matching lines @@
       }
       expect(a.contains(0), isTrue);
       expect(a.contains(5), isTrue);
       expect(a.contains(1023), isTrue);
 
       expect(a.contains(-5), isFalse);
       expect(a.contains(-1), isFalse);
       expect(a.contains(1024), isFalse);
     });
 }