Preserve type variables in closure conversion.

pkg/kernel/testcases/closures_type_vars/type_variables.dart

Index: pkg/kernel/testcases/closures_type_vars/type_variables.dart
diff --git a/pkg/kernel/testcases/closures/type_variables.dart b/pkg/kernel/testcases/closures_type_vars/type_variables.dart
similarity index 87%
rename from pkg/kernel/testcases/closures/type_variables.dart
rename to pkg/kernel/testcases/closures_type_vars/type_variables.dart
index 5883e7372d6e9555d17b909df0db6f4ba372eca6..2de2994f3f9d41e6a8a97eb53c4500310b5755e9 100644
--- a/pkg/kernel/testcases/closures/type_variables.dart
+++ b/pkg/kernel/testcases/closures_type_vars/type_variables.dart
@@ -29,6 +29,15 @@ class C<T, S> {
   C.internal();
 }
 
+fn<A>(A x) {
+  var fn2 = (A x2) {
+    var l = <A>[];
+    l.add(x2);
+    return l;
+  };
+  return fn2(x);
+}
+
 main(arguments) {
   print(new C<String, String>().foo(null)(arguments.first));
   dynamic c = new C<int, int>().baz()()();
@@ -37,4 +46,5 @@ main(arguments) {
     throw "$c passes type test 'is C<String, String>'";
   }
   print(c);
+  print(fn<int>(3));
 }