Fix inferInvocation for top level inference.

pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart

Index: pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
index c5d9d0d29cfa048642c9a31486df5a3792d8de78..eadb02e21af695fdfa8bd0822d8e07d27b8aa145 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inferrer.dart
@@ -370,7 +370,7 @@ abstract class TypeInferrerImpl extends TypeInferrer {
     }
     // TODO(paulberry): if we are doing top level inference and type arguments
     // were omitted, report an error.
-    if (inferenceNeeded || !isTopLevel) {
+    if (!isTopLevel) {
       int i = 0;
       _forEachArgument(arguments, (name, expression) {
         DartType formalType = name != null