Change HashMap declarations back to Map.

pkg/analysis_server/lib/src/resource.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 resource;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:io' as io;
 
@@ skipping 288 matching lines @@
     return streamController.stream;
   }
 }
 
 
 /**
  * An in-memory implementation of [ResourceProvider].
  * Use `/` as a path separator.
  */
 class MemoryResourceProvider implements ResourceProvider {
-  final HashMap<String, _MemoryResource> _pathToResource =
+  final Map<String, _MemoryResource> _pathToResource =
       new HashMap<String, _MemoryResource>();
-  final HashMap<String, String> _pathToContent = new HashMap<String, String>();
-  final HashMap<String, int> _pathToTimestamp = new HashMap<String, int>();
-  final HashMap<String, List<StreamController<WatchEvent>>> _pathToWatchers =
+  final Map<String, String> _pathToContent = new HashMap<String, String>();
+  final Map<String, int> _pathToTimestamp = new HashMap<String, int>();
+  final Map<String, List<StreamController<WatchEvent>>> _pathToWatchers =
       new HashMap<String, List<StreamController<WatchEvent>>>();
   int nextStamp = 0;
 
   @override
   Resource getResource(String path) {
     path = posix.normalize(path);
     Resource resource = _pathToResource[path];
     if (resource == null) {
       resource = new _MemoryFile(this, path);
     }
@@ skipping 232 matching lines @@
   }
 
   /**
    * Return `true` if the given URI is a `file` URI.
    *
    * @param uri the URI being tested
    * @return `true` if the given URI is a `file` URI
    */
   static bool _isFileUri(Uri uri) => uri.scheme == _FILE_SCHEME;
 }