GitLab

Removes /deep/ usage, which no longer works in Shadow DOM v1. Also fixes
some test timing that caused part of the failures.

Bug: 875505,860069
Change-Id: I5642105a6df148bdea2d02b8e1af8889f400c89d
Reviewed-on: https://chromium-review.googlesource.com/1217026Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Demetrios Papadopoulos <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590171}