diff -r 000000000000 -r 6474c204b198 browser/components/customizableui/test/browser_995164_registerArea_during_customize_mode.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/customizableui/test/browser_995164_registerArea_during_customize_mode.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,143 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const TOOLBARID = "test-toolbar-added-during-customize-mode";
+
+add_task(function*() {
+  yield startCustomizing();
+  let toolbar = createToolbarWithPlacements(TOOLBARID, []);
+  CustomizableUI.addWidgetToArea("sync-button", TOOLBARID);
+  let syncButton = document.getElementById("sync-button");
+  ok(syncButton, "Sync button should exist.");
+  is(syncButton.parentNode.localName, "toolbarpaletteitem", "Sync button's parent node should be a wrapper.");
+
+  simulateItemDrag(syncButton, gNavToolbox.palette);
+  ok(!CustomizableUI.getPlacementOfWidget("sync-button"), "Button moved to the palette");
+  ok(gNavToolbox.palette.querySelector("#sync-button"), "Sync button really is in palette.");
+
+  simulateItemDrag(syncButton, toolbar);
+  ok(CustomizableUI.getPlacementOfWidget("sync-button"), "Button moved out of palette");
+  is(CustomizableUI.getPlacementOfWidget("sync-button").area, TOOLBARID, "Button's back on toolbar");
+  ok(toolbar.querySelector("#sync-button"), "Sync button really is on toolbar.");
+
+  yield endCustomizing();
+  isnot(syncButton.parentNode.localName, "toolbarpaletteitem", "Sync button's parent node should not be a wrapper outside customize mode.");
+  yield startCustomizing();
+
+  is(syncButton.parentNode.localName, "toolbarpaletteitem", "Sync button's parent node should be a wrapper back in customize mode.");
+
+  simulateItemDrag(syncButton, gNavToolbox.palette);
+  ok(!CustomizableUI.getPlacementOfWidget("sync-button"), "Button moved to the palette");
+  ok(gNavToolbox.palette.querySelector("#sync-button"), "Sync button really is in palette.");
+
+  ok(!CustomizableUI.inDefaultState, "Not in default state while toolbar is not collapsed yet.");
+  setToolbarVisibility(toolbar, false);
+  ok(CustomizableUI.inDefaultState, "In default state while toolbar is collapsed.");
+
+  setToolbarVisibility(toolbar, true);
+
+  info("Check that removing the area registration from within customize mode works");
+  CustomizableUI.unregisterArea(TOOLBARID);
+  ok(CustomizableUI.inDefaultState, "Now that the toolbar is no longer registered, should be in default state.");
+  ok(!(new Set(gCustomizeMode.areas)).has(toolbar), "Toolbar shouldn't be known to customize mode.");
+
+  CustomizableUI.registerArea(TOOLBARID, {legacy: true, defaultPlacements: []});
+  CustomizableUI.registerToolbarNode(toolbar, []);
+  ok(!CustomizableUI.inDefaultState, "Now that the toolbar is registered again, should no longer be in default state.");
+  ok((new Set(gCustomizeMode.areas)).has(toolbar), "Toolbar should be known to customize mode again.");
+
+  simulateItemDrag(syncButton, toolbar);
+  ok(CustomizableUI.getPlacementOfWidget("sync-button"), "Button moved out of palette");
+  is(CustomizableUI.getPlacementOfWidget("sync-button").area, TOOLBARID, "Button's back on toolbar");
+  ok(toolbar.querySelector("#sync-button"), "Sync button really is on toolbar.");
+
+  let otherWin = yield openAndLoadWindow({}, true);
+  let otherTB = otherWin.document.createElementNS(kNSXUL, "toolbar");
+  otherTB.id = TOOLBARID;
+  otherTB.setAttribute("customizable", "true");
+  let wasInformedCorrectlyOfAreaAppearing = false;
+  let listener = {
+    onAreaNodeRegistered: function(aArea, aNode) {
+      if (aNode == otherTB) {
+        wasInformedCorrectlyOfAreaAppearing = true;
+      }
+    }
+  };
+  CustomizableUI.addListener(listener);
+  otherWin.gNavToolbox.appendChild(otherTB);
+  ok(wasInformedCorrectlyOfAreaAppearing, "Should have been told area was registered.");
+  CustomizableUI.removeListener(listener);
+
+  ok(otherTB.querySelector("#sync-button"), "Sync button is on other toolbar, too.");
+
+  simulateItemDrag(syncButton, gNavToolbox.palette);
+  ok(!CustomizableUI.getPlacementOfWidget("sync-button"), "Button moved to the palette");
+  ok(gNavToolbox.palette.querySelector("#sync-button"), "Sync button really is in palette.");
+  ok(!otherTB.querySelector("#sync-button"), "Sync button is in palette in other window, too.");
+
+  simulateItemDrag(syncButton, toolbar);
+  ok(CustomizableUI.getPlacementOfWidget("sync-button"), "Button moved out of palette");
+  is(CustomizableUI.getPlacementOfWidget("sync-button").area, TOOLBARID, "Button's back on toolbar");
+  ok(toolbar.querySelector("#sync-button"), "Sync button really is on toolbar.");
+  ok(otherTB.querySelector("#sync-button"), "Sync button is on other toolbar, too.");
+
+  let wasInformedCorrectlyOfAreaDisappearing = false;
+  //XXXgijs So we could be using promiseWindowClosed here. However, after
+  // repeated random oranges, I'm instead relying on onWindowClosed below to
+  // fire appropriately - it is linked to an unload event as well, and so
+  // reusing it prevents a potential race between unload handlers where the
+  // one from promiseWindowClosed could fire before the onWindowClosed
+  // (and therefore onAreaNodeRegistered) one, causing the test to fail.
+  let windowCloseDeferred = Promise.defer();
+  listener = {
+    onAreaNodeUnregistered: function(aArea, aNode, aReason) {
+      if (aArea == TOOLBARID) {
+        is(aNode, otherTB, "Should be informed about other toolbar");
+        is(aReason, CustomizableUI.REASON_WINDOW_CLOSED, "Reason should be correct.");
+        wasInformedCorrectlyOfAreaDisappearing = (aReason === CustomizableUI.REASON_WINDOW_CLOSED);
+      }
+    },
+    onWindowClosed: function(aWindow) {
+      if (aWindow == otherWin) {
+        windowCloseDeferred.resolve(aWindow);
+      } else {
+        info("Other window was closed!");
+        info("Other window title: " + (aWindow.document && aWindow.document.title));
+        info("Our window title: " + (otherWin.document && otherWin.document.title));
+      }
+    },
+  };
+  CustomizableUI.addListener(listener);
+  otherWin.close();
+  let windowClosed = yield windowCloseDeferred.promise;
+
+  is(windowClosed, otherWin, "Window should have sent onWindowClosed notification.");
+  ok(wasInformedCorrectlyOfAreaDisappearing, "Should be told about window closing.");
+  // Closing the other window should not be counted against this window's customize mode:
+  is(syncButton.parentNode.localName, "toolbarpaletteitem", "Sync button's parent node should still be a wrapper.");
+  isnot(gCustomizeMode.areas.indexOf(toolbar), -1, "Toolbar should still be a customizable area for this customize mode instance.");
+
+  yield gCustomizeMode.reset();
+
+  yield endCustomizing();
+
+  CustomizableUI.removeListener(listener);
+  wasInformedCorrectlyOfAreaDisappearing = false;
+  listener = {
+    onAreaNodeUnregistered: function(aArea, aNode, aReason) {
+      if (aArea == TOOLBARID) {
+        is(aNode, toolbar, "Should be informed about this window's toolbar");
+        is(aReason, CustomizableUI.REASON_AREA_UNREGISTERED, "Reason for final removal should be correct.");
+        wasInformedCorrectlyOfAreaDisappearing = (aReason === CustomizableUI.REASON_AREA_UNREGISTERED);
+      }
+    },
+  }
+  CustomizableUI.addListener(listener);
+  removeCustomToolbars();
+  ok(wasInformedCorrectlyOfAreaDisappearing, "Should be told about area being unregistered.");
+  CustomizableUI.removeListener(listener);
+  ok(CustomizableUI.inDefaultState, "Should be fine after exiting customize mode.");
+});