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+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test bug 784410</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" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<p id="display"></p>
+<div id="outer" style="overflow:auto; height:200px; border:2px dotted black; transform: translateY(1px)" onscroll="doneScroll()">
+  <div id="d" style="overflow:auto; height:102px;" onscroll="doneScroll()">
+    <div id="inner" style="height:100.1px; border:1px solid black; background:yellow;">Hello</div>
+  </div>
+  <div style="height:500px;"></div>
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+var sel = window.getSelection();
+var outer = document.getElementById("outer");
+var d = document.getElementById("d");
+var inner = document.getElementById("inner");
+var smoothScrollPref = "general.smoothScroll";
+
+function innerScrollOffset() {
+  return inner.getBoundingClientRect().top - d.getBoundingClientRect().top;
+}
+var innerStartScrollOffset = innerScrollOffset();
+
+var step = 0;
+var wheelAndPaintDone = false;
+async function doneScroll() {
+  ++step;
+  switch (step) {
+  case 1:
+    is(innerScrollOffset(), innerStartScrollOffset, "Inner element should not have scrolled down");
+    ok(outer.scrollTop > 0, "Outer element should have scrolled down");
+
+    outer.scrollTop = 0;
+    break;
+  case 2:
+    // wait until APZ is ready to handle the wheel event, then send it
+    await promiseApzFlushedRepaints();
+    // Wait for paints to flush, so APZ is notified of the new scroll offset.
+    sendWheelAndPaint(inner, 4, 4,
+      { deltaMode: WheelEvent.DOM_DELTA_LINE, deltaY: 1 },
+      function() {
+          wheelAndPaintDone = true;
+          doneTest();
+      });
+    break;
+  case 3:
+    is(innerScrollOffset(), innerStartScrollOffset, "Inner element should not have scrolled down");
+    ok(outer.scrollTop > 0, "Outer element should have scrolled down");
+    
+    doneTest();
+    break;
+  }
+}
+
+function doneTest() {
+  // wait until wheelAndPaintDone has invoked its callback before we end the
+  // test, otherwise we might get calls to advanceTimeAndRefresh after we
+  // restore normal refresh, and that will screw up the next test.
+  if (wheelAndPaintDone && step == 3) {
+    SpecialPowers.DOMWindowUtils.restoreNormalRefresh();
+    SimpleTest.finish();
+  }
+}
+
+function test() {
+  sel.collapse(inner.firstChild, 2);
+  synthesizeKey("KEY_PageDown");
+}
+
+SimpleTest.waitForExplicitFinish();
+SimpleTest.waitForFocus(function() {
+  SpecialPowers.pushPrefEnv({"set":[[smoothScrollPref, false],
+                                    ["test.events.async.enabled", true]]}, test);
+});
+</script>
+</pre>
+</body>
+</html>