Move remaining functionality from ClassWorld to ClosedWorld

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

Index: pkg/compiler/lib/src/ssa/types.dart
diff --git a/pkg/compiler/lib/src/ssa/types.dart b/pkg/compiler/lib/src/ssa/types.dart
index edffc3a1664d35e909a8b7c025e9e64b57f784e9..18ed76ca5aa1d01aec330ba9fc03f05fd0ab6aa5 100644
--- a/pkg/compiler/lib/src/ssa/types.dart
+++ b/pkg/compiler/lib/src/ssa/types.dart
@@ -9,7 +9,7 @@ import '../native/native.dart' as native;
 import '../tree/tree.dart' as ast;
 import '../types/types.dart';
 import '../universe/selector.dart' show Selector;
-import '../world.dart' show ClassWorld;
+import '../world.dart' show ClosedWorld;
 
 class TypeMaskFactory {
   static TypeMask inferredReturnTypeForElement(
@@ -34,7 +34,7 @@ class TypeMaskFactory {
     var typesReturned = nativeBehavior.typesReturned;
     if (typesReturned.isEmpty) return compiler.commonMasks.dynamicType;
 
-    ClassWorld world = compiler.closedWorld;
+    ClosedWorld world = compiler.closedWorld;
     CommonMasks commonMasks = compiler.commonMasks;
     CoreClasses coreClasses = compiler.coreClasses;