Update unittest to new package layout.

pkg/intl/test/bidi_format_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('bidi_format_test');
 
+// TODO(rnystrom): Use "package:" URL (#4968).
 #import('../intl.dart');
-#import('../../../pkg/unittest/unittest.dart');
+#import('../../../pkg/unittest/lib/unittest.dart');
 
 /**
  * Tests the bidirectional text formatting library.
  */
 main() {
   var LTR = TextDirection.LTR;
   var RTL = TextDirection.RTL;
   var UNKNOWN = TextDirection.UNKNOWN;
   var he = '\u05e0\u05e1';
   var en = 'abba';
@@ skipping 182 matching lines @@
     expect(rtlFmt.wrapWithUnicode(he, direction : TextDirection.LTR),
         equals('$LRE$he$PDF$RLM'));
     // Test supposed overall dir (LTR) doesn't match context dir (unknown).
     expect(unkFmt.wrapWithUnicode(he, direction : TextDirection.LTR),
         equals('$LRE$he$PDF'));
     // Test supposed overall dir (neutral) doesn't match context dir (LTR).
     expect(ltrFmt.wrapWithUnicode(he, direction : TextDirection.UNKNOWN),
         equals('$he$LRM'));
   });
 }