Reland "[LayoutNG] Remove spaces before <br> to avoid crbug.com/40634"

This is a reland of 6ec9b32f0008c9cdafa6402aefdb3846b3838e50

Mac Retina bots were down when rebaselined last time, and
they started failing when back.

Original change's description:
> [LayoutNG] Remove spaces before <br> to avoid crbug.com/40634
>
> This patch removes spaces before <br> because the images do
> not match due to crbug.com/40634, which LayoutNG does not
> have the problem.
>
> TBR=eae@chromium.org
>
> Bug: 591099
> Change-Id: I8f0770f8911ce2d5c6f9e37ff90752011b84cb49
> Reviewed-on: https://chromium-review.googlesource.com/1142050
> Reviewed-by: Koji Ishii <kojii@chromium.org>
> Commit-Queue: Koji Ishii <kojii@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#576333}

TBR=eae@chromium.org

Bug: 591099
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_layout_ng
Change-Id: I2243c930a20a1b2404854df09fbdeec4a33c9807
Reviewed-on: https://chromium-review.googlesource.com/1149640
Reviewed-by: Koji Ishii <kojii@chromium.org>
Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#577913}
11 files changed