tree 7ace542f9d28c37217f69c8f2835ff64841778d6
parent 8b89288a1d57ddc591cee2e9167fa68df0964895
author Chris Masone <cmasone@chromium.org> 1424798794 -0800
committer ChromeOS Commit Bot <chromeos-commit-bot@chromium.org> 1425087069 +0000

login: Wait for all descendants in browser process group

Since kernel 3.4, it's been possible for a process to wait on all
descendants, not just direct children, given the appropriate prctl().

The session_manager has always wanted to do this, so let's do it!

BUG=chromium:436549
TEST=bvt-inline, unittests

Change-Id: I7d2048cd11762d077f346c0d6e473ba9307c779d
Previous-Reviewed-on: https://chromium-review.googlesource.com/252803
Trybot-Ready: Chris Masone <cmasone@chromium.org>
(cherry picked from commit 1ebe027077ef6a2e0c090143bc5179a7f3531e62)
Reviewed-on: https://chromium-review.googlesource.com/253791
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>
Tested-by: Yuly Novikov <ynovikov@chromium.org>