[cros, multi-profile] Make sure that edge case handling flows work in multi-profiles sign in

BUG=327885

Review URL: https://codereview.chromium.org/151393002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248309 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 248309