Remove Compiler access from ResolutionEnqueuer

pkg/compiler/lib/src/types/union_type_mask.dart

 // Copyright (c) 2013, 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.
 
 part of masks;
 
 class UnionTypeMask implements TypeMask {
   final Iterable<FlatTypeMask> disjointMasks;
 
   static const int MAX_UNION_LENGTH = 4;
@@ skipping 316 matching lines @@
 
   bool needsNoSuchMethodHandling(Selector selector, ClosedWorld closedWorld) {
     return disjointMasks
         .any((e) => e.needsNoSuchMethodHandling(selector, closedWorld));
   }
 
   bool canHit(Element element, Selector selector, ClosedWorld closedWorld) {
     return disjointMasks.any((e) => e.canHit(element, selector, closedWorld));
   }
 
-  Element locateSingleElement(Selector selector, Compiler compiler) {
+  Element locateSingleElement(Selector selector, ClosedWorld closedWorld) {
     Element candidate;
     for (FlatTypeMask mask in disjointMasks) {
-      Element current = mask.locateSingleElement(selector, compiler);
+      Element current = mask.locateSingleElement(selector, closedWorld);
       if (current == null) {
         return null;
       } else if (candidate == null) {
         candidate = current;
       } else if (candidate != current) {
         return null;
       }
     }
     return candidate;
   }
@@ skipping 24 matching lines @@
   int get hashCode {
     int hashCode = isNullable ? 86 : 43;
     // The order of the masks in [disjointMasks] must not affect the
     // hashCode.
     for (var mask in disjointMasks) {
       hashCode = (hashCode ^ mask.nonNullable().hashCode) & 0x3fffffff;
     }
     return hashCode;
   }
 }