diff -r 000000000000 -r 6474c204b198 dom/browser-element/mochitest/browserElement_CloseApp.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/browser-element/mochitest/browserElement_CloseApp.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,72 @@
+/* Any copyright is dedicated to the public domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// Bug 789392 - Test that apps frames can trigger mozbrowserclose by calling
+// window.close(), but browser frames cannot.
+"use strict";
+
+SimpleTest.waitForExplicitFinish();
+browserElementTestHelpers.setEnabledPref(true);
+browserElementTestHelpers.addPermission();
+SpecialPowers.addPermission("embed-apps", true, window.document);
+
+addEventListener('unload', function() {
+  SpecialPowers.removePermission("embed-apps", window.document);
+});
+
+function runTest() {
+  // Our app frame and browser frame load the same content.  That content calls
+  // window.close() and then alert().  We should get a mozbrowserclose event on
+  // the app frame before the mozbrowsershowmodalprompt, but not on the browser
+  // frame.
+
+  var appFrame = document.createElement('iframe');
+  SpecialPowers.wrap(appFrame).mozbrowser = true;
+  appFrame.setAttribute('mozapp', 'http://example.org/manifest.webapp');
+
+  var browserFrame = document.createElement('iframe');
+  SpecialPowers.wrap(browserFrame).mozbrowser = true;
+
+  var gotAppFrameClose = false;
+  appFrame.addEventListener('mozbrowserclose', function() {
+    ok(true, "Got close from app frame.");
+    gotAppFrameClose = true;
+  });
+
+  var gotAppFrameAlert = false;
+  appFrame.addEventListener('mozbrowsershowmodalprompt', function() {
+    ok(gotAppFrameClose, "Should have gotten app frame close by now.");
+    ok(!gotAppFrameAlert, "Just one alert from the app frame.");
+    gotAppFrameAlert = true;
+    if (gotBrowserFrameAlert && gotAppFrameAlert) {
+      SimpleTest.finish();
+    }
+  });
+
+  browserFrame.addEventListener('mozbrowserclose', function() {
+    ok(false, "Got close from browser frame.");
+  });
+
+  var gotBrowserFrameAlert = false;
+  browserFrame.addEventListener('mozbrowsershowmodalprompt', function() {
+    ok(!gotBrowserFrameAlert, "Just one browser frame alert.");
+    gotBrowserFrameAlert = true;
+    if (gotBrowserFrameAlert && gotAppFrameAlert) {
+      SimpleTest.finish();
+    }
+  });
+
+  document.body.appendChild(appFrame);
+  document.body.appendChild(browserFrame);
+
+  appFrame.src = 'http://example.org/tests/dom/browser-element/mochitest/file_browserElement_CloseApp.html';
+  browserFrame.src = 'http://example.org/tests/dom/browser-element/mochitest/file_browserElement_CloseApp.html';
+}
+
+// The test harness sets dom.allow_scripts_to_close_windows to true (as of
+// writing, anyway).  But that means that browser tabs can close themselves,
+// which is what we want to test /can't/ happen!   For the purposes of this
+// test (and normal browser operation), this pref should be false.
+addEventListener('testready', function() {
+  SpecialPowers.pushPrefEnv({'set': [['dom.allow_scripts_to_close_windows', false]]}, runTest);
+});