add a test case for both expression and types

Author: bobzhang

jscomp/test/arity.js

@@ -27,9 +27,16 @@ function h(u) {
   return m(1, 2);
 }
 
+var nested = {
+  x: {
+    y: 3
+  }
+};
+
 exports.u = u;
 exports.u2 = u2;
 exports.f = f;
 exports.add = add;
 exports.h = h;
+exports.nested = nested;
 /* No side effect */

jscomp/test/arity.re

@@ -59,4 +59,7 @@ let u = obj => {
 let h = u => {
     let m = u##hi ;
     m(.1,2);
-}
+}
+
+ // 
+let nested   = ({ "x" : {"y" : 3 }} : {. "x" : {. "y" : int }})