Further reduce use of Compiler.closedWorld.

tests/compiler/dart2js/simple_inferrer_const_closure5_test.dart

Index: tests/compiler/dart2js/simple_inferrer_const_closure5_test.dart
diff --git a/tests/compiler/dart2js/simple_inferrer_const_closure5_test.dart b/tests/compiler/dart2js/simple_inferrer_const_closure5_test.dart
index a41c254ed02e6a30455efc9eb3b6715b5331eb91..41b5febcecbc62e17450dbbc4cdd0e6f7e98820e 100644
--- a/tests/compiler/dart2js/simple_inferrer_const_closure5_test.dart
+++ b/tests/compiler/dart2js/simple_inferrer_const_closure5_test.dart
@@ -30,6 +30,7 @@ void main() {
   var compiler = compilerFor(TEST, uri);
   asyncTest(() => compiler.run(uri).then((_) {
         var typesInferrer = compiler.globalInference.typesInferrerInternal;
+        var closedWorld = typesInferrer.closedWorld;
 
         checkArgument(String functionName, type) {
           var functionElement = findElement(compiler, functionName);
@@ -37,10 +38,10 @@ void main() {
           var element = signature.requiredParameters.first;
           Expect.equals(
               type,
-              simplify(typesInferrer.getTypeOfElement(element), compiler),
+              simplify(typesInferrer.getTypeOfElement(element), closedWorld),
               functionName);
         }
 
-        checkArgument('method', compiler.closedWorld.commonMasks.numType);
+        checkArgument('method', typesInferrer.closedWorld.commonMasks.numType);
       }));
 }