Revert 234430 "kiosk: Remove cryptohome migration code."

It fails compile on chromeos/clang bot.
> kiosk: Remove cryptohome migration code.
> 
> BUG=265506
> 
> Review URL: https://codereview.chromium.org/69333003

TBR=xiyuan@chromium.org

Review URL: https://codereview.chromium.org/68643004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234451 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 234451