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<!DOCTYPE html>
<html lang="en" class="reftest-wait">
<meta charset="utf-8">
<title>This test fails - Layerization should respect overflow:hidden clips around things with animated position</title>

<style>

div {
  min-height: 50px;
  box-model: border-box;
}

.first, .second {
  border: 1px solid blue;
  margin: 50px 0;
  position: relative;
}

.border {
  border: 1px solid black;
}

.underlap {
  border: 1px solid #088;
  margin-left: 120px;
  width: 80px;
  margin-bottom: -30px;
}

.clip {
  height: auto;
  overflow: hidden;
  padding: 10px 0 20px;
}

.animated-position {
  position: relative;
  left: 20px;
  margin-left: 220px;
  width: 100px;
  height: 100px;
  border-color: red;
}

body {
  margin: 0;
  padding: 0 100px;
  height: 3000px;
}

</style>

<div class="first" reftest-assigned-layer="page-background">
  <!--
    This is just a regular box, it should end up in the page background layer.
  -->
</div>

<div class="underlap">
  <!--
    This item intersects with the scrollable box and is positioned below
    .scrollable, in z-order.
  -->
</div>

<div class="clip border">
  <div class="border animated-position reftest-no-paint">
    <!--
      This box starts out above solid white background, but it will move so
      that it intersects .underlap, so it shouldn't pull up a background
      color to begin with so that it doesn't need to invalidate.
    -->
  </div>
</div>

<div class="second" reftest-assigned-layer="page-background">
  <!--
    This should share a layer with .first and the page background.
    However, we don't take .animated-position's clip into account when
    layerizing, so .second will be pulled up into its own layer above
    .animated-position. So this test will fail.
  -->
</div>

<script>

var animatedLeft = document.querySelector(".animated-position");

function doTest() {
  animatedLeft.style.left = "-40px";
  document.documentElement.removeAttribute("class");
}

// Layerize #animatedLeft
animatedLeft.offsetLeft;
animatedLeft.style.left = "40px";
animatedLeft.offsetLeft;
animatedLeft.style.left = "60px";
animatedLeft.offsetLeft;

document.addEventListener("MozReftestInvalidate", doTest);
setTimeout(doTest, 200);

</script>