Convert fast/inline/dirtyLinesForInline.html with W3C testharness

This patch converts the layout test with W3C testharness so that
it doesn't rely on text dump comparison.

This is also a preparation for using element.innerText as text
dump; otherwise, this test generates different innerText dumps on
different platforms (crrev.com/c/1318149), which is undesired.

Bug: 887148
Change-Id: Ic279b9362ff054eb13f847e111baef37d0ef79e3
Reviewed-on: https://chromium-review.googlesource.com/c/1323890
Reviewed-by: Kent Tamura <tkent@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606313}
2 files changed