diff -r 000000000000 -r 6474c204b198 dom/tests/mochitest/whatwg/browserFu.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/tests/mochitest/whatwg/browserFu.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,6 @@
+/**
+ * File which includes stuff for Mozilla-specific checks which shouldn't happen
+ * in other browsers but which we wish to test.
+ */
+
+var isMozilla = navigator.product === "Gecko" && "buildID" in navigator;