From b8a3cfd15d1574261032abb2fb9ffe24f76539ab Mon Sep 17 00:00:00 2001
From: Edgar Chen <echen@mozilla.com>
Date: Wed, 27 Jan 2021 20:31:44 +0000
Subject: [PATCH] Bug 1648435 - Make
 dom/events/test/test_mouse_enterleave_iframe.html waiting apz stable before
 starting tests; r=smaug

This test uses synthesizeNativeMouseMove to synthesize mouse events, the synthesized
native events would go through apz, so wait apz getting stable before starting test
to avoid possible timing problem that causes intermittent failure.

Differential Revision: https://phabricator.services.mozilla.com/D103192
---
 dom/events/test/test_mouse_enterleave_iframe.html | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/dom/events/test/test_mouse_enterleave_iframe.html b/dom/events/test/test_mouse_enterleave_iframe.html
index ee4b4f6fc13e..8a275a997c28 100644
--- a/dom/events/test/test_mouse_enterleave_iframe.html
+++ b/dom/events/test/test_mouse_enterleave_iframe.html
@@ -3,6 +3,8 @@
 <title>Test mouseenter and mouseleave for iframe.</title>
 <script src="/tests/SimpleTest/SimpleTest.js"></script>
 <script src="/tests/SimpleTest/EventUtils.js"></script>
+<script src="/tests/SimpleTest/paint_listener.js"></script>
+<script src="/tests/gfx/layers/apz/test/mochitest/apz_test_utils.js"></script>
 <link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
 <style>
 #start {
@@ -157,6 +159,9 @@ add_task(async function init() {
   // Wait for focus before starting tests.
   await SimpleTest.promiseFocus();
 
+  // Wait for apz getting stable.
+  await waitUntilApzStable();
+
   // Move mouse to initial position.
   await moveMouseToInitialPosition();
 });
@@ -262,6 +267,8 @@ add_task(async function testMouseEnterLeaveSwitchWindow() {
   win.close();
   // Trigger a reflow which will generate synthesized mouse move event.
   reflow();
+  // Wait for apz getting stable.
+  await waitUntilApzStable();
   synthesizeNativeMouseMove(target, targetRect.width / 2, targetRect.height / 2);
   await promise;