GitLab

Adds new WPT reftest testing the styling of ::before and ::after
pseudo-elements within a ::first-line pseudo-element.
This currently fails in chromium and passes in firefox.

Bug: 892983
Change-Id: If15b4004b8091fa0871e580dc2f059a69174546a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1900391Reviewed-by: Stephen McGruer <smcgruer@chromium.org>
Commit-Queue: George Steel <gtsteel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#713535}