commit 69f0712961a7ec8aedcd3ee724fa23c1aa8175fc
author mstensho <mstensho@opera.com> Mon Sep 12 09:54:18 2016
committer Commit bot <commit-bot@chromium.org> Mon Sep 12 09:56:29 2016
tree 6d2c5a61621f2bde4f9241f235dbe0c58acc7a7c
parent cc85d7601e6932050d2a12d3c03ffb8329969e92

A container of out-of-flow positioned descendants should be an offsetParent.

This reflects a recent spec change [1]. Previously, the condition was that the
position property be different from 'static', but it's unreasonable that we
shouldn't also include other objects that serve as containing blocks for fixed
and absolutely positioned descendants, such as "transform". Gecko and Edge
already have this behavior.

[1] https://github.com/w3c/csswg-drafts/commit/180b348a1ac0931043cd195651fc5164463d2bce

BUG=645397

Review-Url: https://codereview.chromium.org/2328633003
Cr-Commit-Position: refs/heads/master@{#417903}