Change Maps to HashMaps to save in performance, index and generated directories not touched

pkg/analysis_server/test/package_uri_resolver_test.dart

 // Copyright (c) 2014, 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 test.resolver.package;
 
+import 'dart:collection';
+
 import 'package:analysis_server/src/package_uri_resolver.dart';
 import 'package:analysis_server/src/resource.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:unittest/unittest.dart';
 
 import 'reflective_tests.dart';
 
 main() {
   groupSep = ' | ';
 
   group('PackageMapUriResolver', () {
     runReflectiveTests(_PackageMapUriResolverTest);
   });
 }
 
 
 @ReflectiveTestCase()
 class _PackageMapUriResolverTest {
-  static const EMPTY_MAP = const <String, List<Folder>>{};
+  static HashMap EMPTY_MAP = new HashMap<String, List<Folder>>();
   MemoryResourceProvider provider = new MemoryResourceProvider();
 
   setUp() {
   }
 
   tearDown() {
   }
 
   void test_isPackageUri() {
     Uri uri = Uri.parse('package:test/test.dart');
@@ skipping 114 matching lines @@
 
   void test_resolve_package_notInMap() {
     UriResolver resolver = new PackageMapUriResolver(provider, EMPTY_MAP);
     Uri uri = Uri.parse('package:analyzer/analyzer.dart');
     Source result = resolver.resolveAbsolute(uri);
     expect(result, isNotNull);
     expect(result.exists(), isFalse);
     expect(result.fullName, 'package:analyzer/analyzer.dart');
   }
 }