diff -r 000000000000 -r 6474c204b198 gfx/tests/unit/test_nsIScriptableRegion.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/tests/unit/test_nsIScriptableRegion.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,16 @@
+function run_test()
+{
+  // XXX Work around for the fact that for non-libxul builds loading gfx
+  // components doesn't call up the layout initialisation routine. This should
+  // be fixed/improved by bug 515595.
+  Components.classes["@mozilla.org/layout/xul-boxobject-tree;1"]
+            .createInstance(Components.interfaces.nsIBoxObject);
+
+  let rgn = Components.classes["@mozilla.org/gfx/region;1"].createInstance(Components.interfaces.nsIScriptableRegion);
+  do_check_true (rgn.getRects() === null)
+  rgn.unionRect(0,0,80,60);
+  do_check_true (rgn.getRects().toString() == "0,0,80,60")
+  rgn.unionRect(90,70,1,1);
+  do_check_true (rgn.getRects().toString() == "0,0,80,60,90,70,1,1")
+}
+