diff -r 000000000000 -r 6474c204b198 browser/base/content/test/general/browser_bug484315.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/base/content/test/general/browser_bug484315.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,23 @@
+function test() {
+  var contentWin = window.open("about:blank", "", "width=100,height=100");
+  var enumerator = Services.wm.getEnumerator("navigator:browser");
+
+  while (enumerator.hasMoreElements()) {
+    let win = enumerator.getNext();
+    if (win.content == contentWin) {
+      gPrefService.setBoolPref("browser.tabs.closeWindowWithLastTab", false);
+      win.gBrowser.removeCurrentTab();
+      ok(win.closed, "popup is closed");
+
+      // clean up
+      if (!win.closed)
+        win.close();
+      if (gPrefService.prefHasUserValue("browser.tabs.closeWindowWithLastTab"))
+        gPrefService.clearUserPref("browser.tabs.closeWindowWithLastTab");
+
+      return;
+    }
+  }
+
+  throw "couldn't find the content window";
+}