GitLab

Adding an additional div container on top of the "customize this page"
dialog can make sure the dialog will close only when we click outside
the dialog. Also, clicking on the disabled option will no longer close
the dialog.

Bug: 874828
Change-Id: Ibe16d3e898feefa716cf09e49a52c8a788de254c
Reviewed-on: https://chromium-review.googlesource.com/1195716Reviewed-by: Kristi Park <kristipark@chromium.org>
Commit-Queue: Weilun Shi <sweilun@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587331}