Fix #14144 confusing error message misusing a callable object

runtime/lib/errors_patch.dart

Index: runtime/lib/errors_patch.dart
diff --git a/runtime/lib/errors_patch.dart b/runtime/lib/errors_patch.dart
index cf42b572f7c9a7904b0c590174835b36af7ade8b..fa43b102dacf0c70f744b67091bbba87aeacb8a7 100644
--- a/runtime/lib/errors_patch.dart
+++ b/runtime/lib/errors_patch.dart
@@ -312,7 +312,9 @@ class NoSuchMethodError {
                   .writeln("The $type_str '$memberName' was called on null.");
             }
           } else {
-            if (_receiver is Function) {
+            if (_receiver.runtimeType == Function ||
+                _receiver.runtimeType == _Closure ||
+                (_receiver is Function && memberName.startsWith("call"))) {

[Florian Schneider, 2017/03/30 20:18:05]

I think this should be

(_receiver is Function && memberName == "call")

so that something like "callbar" is handled as expected.

               msg_buf.writeln("Closure call with mismatched arguments: "
                   "function '$memberName'");
             } else if (_receiver is _Type && memberName == "call") {