diff -r 000000000000 -r 6474c204b198 services/sync/tests/tps/test_addon_reconciling.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/services/sync/tests/tps/test_addon_reconciling.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,51 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// This test verifies that record reconciling works as expected. It makes
+// similar changes to add-ons in separate profiles and does a sync to verify
+// the proper action is taken.
+EnableEngines(["addons"]);
+
+let phases = {
+  "phase01": "profile1",
+  "phase02": "profile2",
+  "phase03": "profile1",
+  "phase04": "profile2",
+  "phase05": "profile1",
+  "phase06": "profile2"
+};
+
+const id = "restartless-xpi@tests.mozilla.org";
+
+// Install the add-on in 2 profiles.
+Phase("phase01", [
+  [Addons.verifyNot, [id]],
+  [Addons.install, [id]],
+  [Addons.verify, [id], STATE_ENABLED],
+  [Sync]
+]);
+Phase("phase02", [
+  [Addons.verifyNot, [id]],
+  [Sync],
+  [Addons.verify, [id], STATE_ENABLED]
+]);
+
+// Now we disable in one and uninstall in the other.
+Phase("phase03", [
+  [Sync], // Get GUID updates, potentially.
+  [Addons.setEnabled, [id], STATE_DISABLED],
+]);
+Phase("phase04", [
+  [EnsureTracking],
+  [Addons.uninstall, [id]],
+  [Sync]
+]);
+
+// When we sync, the uninstall should take precedence because it was newer.
+Phase("phase05", [
+  [Sync]
+]);
+Phase("phase06", [
+  [Sync],
+  [Addons.verifyNot, [id]]
+]);