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

pkg/unittest/test/matchers_test.dart

Index: pkg/unittest/test/matchers_test.dart
===================================================================
--- pkg/unittest/test/matchers_test.dart	(revision 14413)
+++ pkg/unittest/test/matchers_test.dart	(working copy)
@@ -2,9 +2,9 @@
 // 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('matcherTest');
-#import('../../../pkg/unittest/unittest.dart');
-#source('test_utils.dart');
+library unittestTests;
+import '../../../pkg/unittest/lib/unittest.dart';
+part 'test_utils.dart';
 
 doesNotThrow() {}
 doesThrow() { throw 'X'; }
@@ -126,13 +126,12 @@
     });
 
     test('throwsRangeError', () {
-      shouldPass(() { throw new RangeError.value(0); },
+      shouldPass(() { throw new RangeError(0); },
           throwsRangeError);
       shouldFail(() { throw new Exception(); },
           throwsRangeError,
         "Expected: throws an exception which matches RangeError "
-        "but:  exception <Exception> does not match "
-            "RangeError.");
+        "but:  exception <Exception> does not match RangeError.");
     });
 
     test('throwsNoSuchMethodError', () {