Fix for URI resolution w/ file scheme set in package map.

pkg/analyzer/test/generated/source_factory_test.dart

 // Copyright (c) 2015, 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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library analyzer.test.generated.source_factory;
 
 import 'dart:convert';
@@ skipping 59 matching lines @@
     }
     SourceFactory factory = new SourceFactory(resolvers, packages);
     return factory.restoreUri(source);
   }
 
   group('SourceFactoryTest', () {
     group('package mapping', () {
       group('resolveUri', () {
         test('URI in mapping', () {
           String uri = resolvePackageUri(config: '''
+unittest:file:///home/somebody/.pub/cache/unittest-0.9.9/lib/
+async:file:///home/somebody/.pub/cache/async-1.1.0/lib/
+quiver:file:///home/somebody/.pub/cache/quiver-1.2.1/lib
+''', uri: 'package:unittest/unittest.dart');
+          expect(uri, equals(
+              '/home/somebody/.pub/cache/unittest-0.9.9/lib/unittest.dart'));
+        });
+        test('URI in mapping (no scheme)', () {
+          String uri = resolvePackageUri(config: '''
 unittest:/home/somebody/.pub/cache/unittest-0.9.9/lib/
 async:/home/somebody/.pub/cache/async-1.1.0/lib/
 quiver:/home/somebody/.pub/cache/quiver-1.2.1/lib
 ''', uri: 'package:unittest/unittest.dart');
           expect(uri, equals(
               '/home/somebody/.pub/cache/unittest-0.9.9/lib/unittest.dart'));
         });
         test('URI not in mapping', () {
           String uri = resolvePackageUri(
               config: 'unittest:/home/somebody/.pub/cache/unittest-0.9.9/lib/',
@@ skipping 226 matching lines @@
   UriResolver_SourceFactoryTest_test_fromEncoding_valid(this.encoding);
 
   @override
   Source resolveAbsolute(Uri uri) {
     if (uri.toString() == encoding) {
       return new TestSource();
     }
     return null;
   }
 }