Apply patch from other client.

utils/pub/package.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 package;
 
 import 'io.dart';
 import 'pubspec.dart';
 import 'source.dart';
 import 'source_registry.dart';
 import 'version.dart';
 
 /**
  * A named, versioned, unit of code and resource reuse.
  */
 class Package {
   /**
    * Loads the package whose root directory is [packageDir]. [name] is the
    * expected name of that package (e.g. the name given in the dependency), or
    * null if the package being loaded is the entrypoint package.
    */
   static Future<Package> load(String name, String packageDir,
       SourceRegistry sources) {
     var pubspecPath = join(packageDir, 'pubspec.yaml');
 
     return fileExists(pubspecPath).chain((exists) {
       if (!exists) throw new PubspecNotFoundException(name);
       return readTextFile(pubspecPath);
     }).transform((contents) {
-      var pubspec = new Pubspec.parse(contents, sources);
-      if (pubspec.name == null) throw new PubspecHasNoNameException(name);
-      if (name != null && pubspec.name != name) {
-        throw new PubspecNameMismatchException(name, pubspec.name);
+      try {
+        var pubspec = new Pubspec.parse(contents, sources);
+
+        if (pubspec.name == null) throw new PubspecHasNoNameException(name);
+        if (name != null && pubspec.name != name) {
+          throw new PubspecNameMismatchException(name, pubspec.name);
+        }
+        return new Package._(packageDir, pubspec);
+      } on FormatException catch (ex) {
+        throw 'Could not parse $pubspecPath:\n${ex.message}';
       }
-      return new Package._(packageDir, pubspec);
     });
   }
 
   /**
    * The path to the directory containing the package.
    */
   final String dir;
 
   /**
    * The name of the package.
@@ skipping 167 matching lines @@
 
 class PubspecNameMismatchException implements Exception {
   final String expectedName;
   final String actualName;
 
   PubspecNameMismatchException(this.expectedName, this.actualName);
 
   String toString() => 'The name you specified for your dependency, '
     '"$expectedName", doesn\'t match the name "$actualName" in its pubspec.';
 }