Reduce use of Element in optimize.dart

pkg/compiler/lib/src/universe/world_builder.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 universe;
 
 import 'dart:collection';
 
 import '../cache_strategy.dart';
 import '../common.dart';
@@ skipping 21 matching lines @@
 ///
 ///     class Bar {
 ///        void foo() {}
 ///     }
 ///     main() => new Bar().foo();
 ///
 abstract class ReceiverConstraint {
   /// Returns whether [element] is a potential target when being
   /// invoked on a receiver with this constraint. [selector] is used to ensure
   /// library privacy is taken into account.
-  bool canHit(Element element, Selector selector, World world);
+  bool canHit(MemberElement element, Selector selector, World world);
 
   /// Returns whether this [TypeMask] applied to [selector] can hit a
   /// [noSuchMethod].
   bool needsNoSuchMethodHandling(Selector selector, World world);
 }
 
 /// The combined constraints on receivers all the dynamic call sites of the same
 /// selector.
 ///
 /// For instance for these calls
@@ skipping 1913 matching lines @@
   @override
   EnumSet<MemberUse> get _originalUse => MemberUses.ALL_STATIC;
 }
 
 void removeFromSet(Map<String, Set<_MemberUsage>> map, Element element) {
   Set<_MemberUsage> set = map[element.name];
   if (set == null) return;
   set.removeAll(
       set.where((_MemberUsage usage) => usage.entity == element).toList());
 }