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

pkg/intl/test/data_directory.dart

Index: pkg/intl/test/data_directory.dart
===================================================================
--- pkg/intl/test/data_directory.dart	(revision 14313)
+++ pkg/intl/test/data_directory.dart	(working copy)
@@ -7,9 +7,9 @@
  * simple cases) for file-dependent programs being run from different
  * directories.
  */
-#library('data_directory');
+library data_directory;
 
-#import('dart:io');
+import 'dart:io';
 
 String get _sep => Platform.pathSeparator;
 
@@ -22,4 +22,4 @@
     return 'lib${_sep}src${_sep}data${_sep}dates${_sep}';
   }
   return 'pkg${_sep}intl${_sep}lib${_sep}src${_sep}data${_sep}dates${_sep}';
-}
+}