Change core lib, dart2js, and more for new optional parameters syntax

utils/pub/git_source.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 git_source;
 
 import 'git.dart' as git;
 import 'io.dart';
 import 'package.dart';
 import 'source.dart';
@@ skipping 48 matching lines @@
       if (ref == 'HEAD') return new Future.immediate(null);
       return _checkOut(revisionCachePath, ref);
     }).chain((_) {
       return Package.load(id.name, revisionCachePath, systemCache.sources);
     });
   }
 
   /**
    * Ensures [description] is a Git URL.
    */
-  void validateDescription(description, [bool fromLockFile = false]) {
+  void validateDescription(description, {bool fromLockFile: false}) {
     // A single string is assumed to be a Git URL.
     if (description is String) return;
     if (description is! Map || !description.containsKey('url')) {
       throw new FormatException("The description must be a Git URL or a map "
           "with a 'url' key.");
     }
     description = new Map.from(description);
     description.remove('url');
     description.remove('ref');
     if (fromLockFile) description.remove('resolved-ref');
@@ skipping 137 matching lines @@
 
   /**
    * Returns [description] if it's a description, or [PackageId.description] if
    * it's a [PackageId].
    */
   _getDescription(description) {
     if (description is PackageId) return description.description;
     return description;
   }
 }