Removal of the author portion of the kiosk mode security toast.

As discussed we do not have a company name to display here. Kuscher is happy with removing this from the toast.

BUG=341662
TEST=unittest

Review URL: https://codereview.chromium.org/190973012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256253 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 256253