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

tests/html/typed_arrays_4_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('TypedArrays4Test');
-#import('../../pkg/unittest/unittest.dart');
-#import('../../pkg/unittest/html_config.dart');
-#import('dart:html');
+library TypedArrays4Test;
+import '../../pkg/unittest/lib/unittest.dart';
+import '../../pkg/unittest/lib/html_config.dart';
+import 'dart:html';
 
 main() {
   useHtmlConfiguration();
 
   test('indexOf_dynamic', () {
       var a1 = new Uint8Array(1024);
       for (int i = 0; i < a1.length; i++) {
         a1[i] = i;
       }
 
@@ skipping 14 matching lines @@
 
       expect(a1.indexOf(50), 50);
       expect(a1.indexOf(50, 50), 50);
       expect(a1.indexOf(50, 51), 256 + 50);
 
       expect(a1.lastIndexOf(50), 768 + 50);
       expect(a1.lastIndexOf(50, 768 + 50), 768 + 50);
       expect(a1.lastIndexOf(50, 768 + 50 - 1), 512 + 50);
   });
 }