diff -r 000000000000 -r 6474c204b198 browser/base/content/test/general/browser_homeDrop.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/base/content/test/general/browser_homeDrop.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,91 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function test() {
+  waitForExplicitFinish();
+
+  let str = Cc["@mozilla.org/supports-string;1"]
+              .createInstance(Ci.nsISupportsString);
+  str.data = "about:mozilla";
+  Services.prefs.setComplexValue("browser.startup.homepage",
+                                 Ci.nsISupportsString, str);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("browser.startup.homepage");
+  });
+
+  // Open a new tab, since starting a drag from the home button activates it and
+  // we don't want to interfere with future tests by loading the home page.
+  let newTab = gBrowser.selectedTab = gBrowser.addTab();
+  registerCleanupFunction(function () {
+    gBrowser.removeTab(newTab);
+  });
+
+  let scriptLoader = Cc["@mozilla.org/moz/jssubscript-loader;1"].
+                     getService(Ci.mozIJSSubScriptLoader);
+  let ChromeUtils = {};
+  scriptLoader.loadSubScript("chrome://mochikit/content/tests/SimpleTest/ChromeUtils.js", ChromeUtils);
+
+  let homeButton = document.getElementById("home-button");
+  ok(homeButton, "home button present");
+
+  let dialogListener = new WindowListener("chrome://global/content/commonDialog.xul", function (domwindow) {
+    ok(true, "dialog appeared in response to home button drop");
+    domwindow.document.documentElement.cancelDialog();
+    Services.wm.removeListener(dialogListener);
+
+    // Now trigger the invalid URI test
+    executeSoon(function () {
+      let consoleListener = {
+        observe: function (m) {
+          if (m.message.contains("NS_ERROR_DOM_BAD_URI")) {
+            ok(true, "drop was blocked");
+            executeSoon(finish);
+          }
+        }
+      }
+      Services.console.registerListener(consoleListener);
+      registerCleanupFunction(function () {
+        Services.console.unregisterListener(consoleListener);
+      });
+
+      executeSoon(function () {
+        info("Attempting second drop, of a javascript: URI");
+        // The drop handler throws an exception when dragging URIs that inherit
+        // principal, e.g. javascript:
+        expectUncaughtException();
+        ChromeUtils.synthesizeDrop(homeButton, homeButton, [[{type: "text/plain", data: "javascript:8888"}]], "copy", window);
+      });
+    })
+  });
+
+  Services.wm.addListener(dialogListener);
+
+  ChromeUtils.synthesizeDrop(homeButton, homeButton, [[{type: "text/plain", data: "http://mochi.test:8888/"}]], "copy", window);
+}
+
+function WindowListener(aURL, aCallback) {
+  this.callback = aCallback;
+  this.url = aURL;
+}
+WindowListener.prototype = {
+  onOpenWindow: function(aXULWindow) {
+    var domwindow = aXULWindow.QueryInterface(Ci.nsIInterfaceRequestor)
+                              .getInterface(Ci.nsIDOMWindow);
+    var self = this;
+    domwindow.addEventListener("load", function() {
+      domwindow.removeEventListener("load", arguments.callee, false);
+
+      ok(true, "domwindow.document.location.href: " + domwindow.document.location.href);
+      if (domwindow.document.location.href != self.url)
+        return;
+
+      // Allow other window load listeners to execute before passing to callback
+      executeSoon(function() {
+        self.callback(domwindow);
+      });
+    }, false);
+  },
+  onCloseWindow: function(aXULWindow) {},
+  onWindowTitleChange: function(aXULWindow, aNewTitle) {}
+}
+