Move remaining functionality from ClassWorld to ClosedWorld

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

Index: pkg/compiler/lib/src/types/value_type_mask.dart
diff --git a/pkg/compiler/lib/src/types/value_type_mask.dart b/pkg/compiler/lib/src/types/value_type_mask.dart
index 1ca437bab407430e50adfefa754891d97fb5582b..ba99b0691a33f79b1118d71fe026079414d92257 100644
--- a/pkg/compiler/lib/src/types/value_type_mask.dart
+++ b/pkg/compiler/lib/src/types/value_type_mask.dart
@@ -27,8 +27,8 @@ class ValueTypeMask extends ForwardingTypeMask {
     return super.equalsDisregardNull(other) && value == other.value;
   }
 
-  TypeMask intersection(TypeMask other, ClassWorld classWorld) {
-    TypeMask forwardIntersection = forwardTo.intersection(other, classWorld);
+  TypeMask intersection(TypeMask other, ClosedWorld closedWorld) {
+    TypeMask forwardIntersection = forwardTo.intersection(other, closedWorld);
     if (forwardIntersection.isEmptyOrNull) return forwardIntersection;
     return forwardIntersection.isNullable ? nullable() : nonNullable();
   }