Remove Compiler access from ResolutionEnqueuer

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

Index: pkg/compiler/lib/src/types/masks.dart
diff --git a/pkg/compiler/lib/src/types/masks.dart b/pkg/compiler/lib/src/types/masks.dart
index 857755874582af9790cd26b5ac9ffde06497751b..5cbc4c06dd4df6cc21b90139b16c48b01614fad6 100644
--- a/pkg/compiler/lib/src/types/masks.dart
+++ b/pkg/compiler/lib/src/types/masks.dart
@@ -33,11 +33,9 @@ part 'value_type_mask.dart';
 class CommonMasks {
   // TODO(sigmund): once we split out the backend common elements, depend
   // directly on those instead.
-  final Compiler compiler;
+  final ClosedWorld closedWorld;
 
-  CommonMasks(this.compiler);
-
-  ClosedWorld get closedWorld => compiler.closedWorld;
+  CommonMasks(this.closedWorld);
 
   BackendClasses get backendClasses => closedWorld.backendClasses;