Use unordered map hash on ConstructedConstantValue.

pkg/compiler/lib/src/util/util.dart

 // Copyright (c) 2011, 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 dart2js.util;
 
 import 'util_implementation.dart';
 import 'characters.dart';
 
 export 'setlet.dart';
@@ skipping 34 matching lines @@
   /// Mix the bits of the element hash codes of [list] with [existing].
   static int listHash(List list, [int existing = 0]) {
     int h = existing;
     int length = list.length;
     for (int i = 0; i < length; i++) {
       h = mixHashCodeBits(h, list[i].hashCode);
     }
     return h;
   }
 
+  /// Mix the bits of the hash codes of the unordered key/value from [map] with
+  /// [existing].
+  static int unorderedMapHash(Map map, [int existing = 0]) {
+    int h = 0;
+    for (var key in map.keys) {
+      h ^= objectHash(key, objectHash(map[key]));
+    }
+    return mixHashCodeBits(h, existing);
+  }
+
   /// Mix the bits of the key/value hash codes from [map] with [existing].
   static int mapHash(Map map, [int existing = 0]) {
     int h = existing;
     for (var key in map.keys) {
       h = mixHashCodeBits(h, key.hashCode);
       h = mixHashCodeBits(h, map[key].hashCode);
     }
     return h;
   }
 }
@@ skipping 158 matching lines @@
   if (usedNames.contains(suggestedName)) {
     int counter = 0;
     while (usedNames.contains(result)) {
       counter++;
       result = "$suggestedName$counter";
     }
   }
   usedNames.add(result);
   return result;
 }