GitLab

Updates chromeos::DemoSession to use
chromeos::DIR_PREINSTALLED_COMPONENTS to determine the preinstalled demo
mode resources path.

TEST=existing unittests
BUG=869455

Change-Id: Idd63ae0893b4fa3966d69bb295fbdb0290456bca
Reviewed-on: https://chromium-review.googlesource.com/1180729
Commit-Queue: Toni Baržić <tbarzic@chromium.org>
Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585373}