GitLab

By setting the last selected directory to the user profile after the
user select a custom background image, the user can go to the last
directory instead of going to "This PC" or home directory.

Bugs: 867758
Change-Id: I6b6fb1296a2f1ffb60148522cdd25a1f027f630e
Reviewed-on: https://chromium-review.googlesource.com/1162712Reviewed-by: Mathieu Perreault <mathp@chromium.org>
Commit-Queue: Weilun Shi <sweilun@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580921}