Add missing parameter and reorder actual, expected assertion parameters (#1326)

test/built-ins/BigInt/prototype/Symbol.toStringTag.js

@@ -21,17 +21,17 @@ verifyProperty(BigInt.prototype, Symbol.toStringTag, {
   configurable: true
 });
 
-assert.sameValue("[object BigInt]", Object.prototype.toString.call(3n));
-assert.sameValue("[object BigInt]", Object.prototype.toString.call(Object(3n)));
+assert.sameValue(Object.prototype.toString.call(3n), "[object BigInt]");
+assert.sameValue(Object.prototype.toString.call(Object(3n)), "[object BigInt]");
 
 // Verify that Object.prototype.toString does not have special casing for BigInt
 // as it does for most other primitive types
-Object.defineProperty(BigInt.prototype, {
+Object.defineProperty(BigInt.prototype, Symbol.toStringTag, {
   value: "FooBar",
   writable: false,
   enumerable: false,
   configurable: true
 });
 
-assert.sameValue("[object FooBar]", Object.prototype.toString.call(3n));
-assert.sameValue("[object FooBar]", Object.prototype.toString.call(Object(3n)));
+assert.sameValue(Object.prototype.toString.call(3n), "[object FooBar]");
+assert.sameValue(Object.prototype.toString.call(Object(3n)), "[object FooBar]");