diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/bug686396.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/bug686396.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,16 @@
+
+(function () { 
+  assertEquals = function assertEquals(expected, found, name_opt) {  };
+})();
+function testOne(receiver, key, result) {
+  for(var i = 0; i != 10; i++ ) {
+    assertEquals(result, receiver[key]());
+  }
+}
+function TypeOfThis() { return typeof this; }
+Number.prototype.type = TypeOfThis;
+String.prototype.type = TypeOfThis;
+Boolean.prototype.type = TypeOfThis;
+testOne(2.3, 'type', 'object');
+testOne('x', 'type', 'object');
+testOne(true, 'type', 'object');