Add check for user in cros settings handler

BUG=341969
R=nkostylev@chromium.org

Review URL: https://codereview.chromium.org/169993002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251871 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251871
Fix ProfileChooserView button color regression.

r251624 mistakenly removed this GetSystemColor call.

BUG=344593
TEST=New Profile Management UI buttons have the expected blue background on hover; otherwise look as expected.
TBR=sky@chromium.org,noms@chromium.org

Review URL: https://codereview.chromium.org/166273005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251872 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251872