Fix missing parens around object in MemberExpression (#424)

tests/objects/__snapshots__/jsfmt.spec.js.snap

@@ -46,9 +46,11 @@ var z = Object(123);
 exports[`test expression.js 1`] = `
 "() => ({}\`\`);
 ({})\`\`;
+a = () => ({}).x;
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 (() => ({})\`\`);
 ({})\`\`;
+a = () => ({}).x;
 "
 `;
 

tests/objects/expression.js

@@ -1,2 +1,3 @@
 () => ({}``);
 ({})``;
+a = () => ({}).x;

tests/refinements/__snapshots__/jsfmt.spec.js.snap

@@ -2565,7 +2565,7 @@ let tests = [
     if (x.kind === null.toString()) {
     }
     // error, method on null
-    if ({ kind: 1 }.kind === null.toString()) {
+    if (({ kind: 1 }).kind === null.toString()) {
     } // error, method on null
   },
   // non-objects on LHS