layout/reftests/css-blending/background-blending-image-image-ref.html
author Andrew McCreight <continuation@gmail.com>
Mon, 22 Apr 2019 16:34:51 +0000
changeset 470376 3073770e06f157040f4c64951b7e8425e1ad7bbe
parent 154144 cea821ee6e174e939e752b31e80a01738ed54774
permissions -rw-r--r--
Bug 1535403 - Take indirection into account for the CC optimizations for the outer window wrapper. r=peterv Most wrapper cached C++ objects are held alive by their wrapper. The cycle collector takes advantage of this in many classes and ignores the C++ object if the wrapper is marked black. However, this is not true for the outer window's wrapper. Instead, the outer window's wrapper keeps the inner window alive. The inner window usually keeps its outer window alive, but not after it has been unlinked. For reasons I do not yet understand, the outer window's wrapper can be kept alive after the inner window it is a proxy for is unlinked. This patch fixes the cycle collector optimization for the outer window by only applying it if the outer window still has a weak reference to the inner window, which it will until the inner no longer holds the outer alive. This in turn fixes, or at least helps fix, window leaks seen intermittently when the lifetime of outer windows and docshells are tied together. The code comment is based on a review comment by peterv. Differential Revision: https://phabricator.services.mozilla.com/D27981

<!--
     Any copyright is dedicated to the Public Domain.
     http://creativecommons.org/publicdomain/zero/1.0/
-->
<html>
<style>
.reftest {
  width: 200px;
  height: 200px;
  background-size: 100px 100px, 200px 200px;
  background-repeat: no-repeat;
}

.blend {
  background-image: url(as-image/black100x100.png);
  background-color: rgb(0, 255, 0);
}
</style>
<div class="reftest blend"></div>
</html>