diff -r 000000000000 -r 6474c204b198 toolkit/content/tests/browser/browser_default_image_filename.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/content/tests/browser/browser_default_image_filename.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,56 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+var MockFilePicker = SpecialPowers.MockFilePicker;
+MockFilePicker.init(window);
+
+/**
+ * TestCase for bug 564387
+ * <https://bugzilla.mozilla.org/show_bug.cgi?id=564387>
+ */
+function test() {
+  waitForExplicitFinish();
+  var fileName;
+
+  gBrowser.selectedTab = gBrowser.addTab();
+
+  gBrowser.loadURI("data:image/gif;base64,R0lGODlhEAAOALMAAOazToeHh0tLS/7LZv/0jvb29t/f3//Ub//ge8WSLf/rhf/3kdbW1mxsbP//mf///yH5BAAAAAAALAAAAAAQAA4AAARe8L1Ekyky67QZ1hLnjM5UUde0ECwLJoExKcppV0aCcGCmTIHEIUEqjgaORCMxIC6e0CcguWw6aFjsVMkkIr7g77ZKPJjPZqIyd7sJAgVGoEGv2xsBxqNgYPj/gAwXEQA7");
+
+  registerCleanupFunction(function () {
+    gBrowser.removeCurrentTab();
+  });
+
+  gBrowser.addEventListener("pageshow", function pageShown(event) {
+    if (event.target.location == "about:blank")
+      return;
+    gBrowser.removeEventListener("pageshow", pageShown);
+
+    executeSoon(function () {
+      document.addEventListener("popupshown", contextMenuOpened);
+
+      var img = gBrowser.contentDocument.getElementsByClassName("decoded")[0];
+      EventUtils.synthesizeMouseAtCenter(img,
+                                         { type: "contextmenu", button: 2 },
+                                         gBrowser.contentWindow);
+    });
+  });
+
+  function contextMenuOpened(event) {
+    event.currentTarget.removeEventListener("popupshown", contextMenuOpened);
+
+    MockFilePicker.showCallback = function(fp) {
+      is(fp.defaultString, "index.gif");
+      executeSoon(finish);
+    };
+
+    registerCleanupFunction(function () {
+      MockFilePicker.cleanup();
+    });
+
+    // Select "Save Image As" option from context menu
+    var saveImageAsCommand = document.getElementById("context-saveimage");
+    saveImageAsCommand.doCommand();
+
+    event.target.hidePopup();
+  }
+}