ChromeOS: properly enable multiprofile mode in LoginManagerTest.

Fix some tests that fail when it is enabled.

BUG=326832

Review URL: https://codereview.chromium.org/110913009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242068 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242068