Update account list on account picker activity resume

Activities which help select an account gather the list of accounts only during create and dont update it agian. When a user moves out of the account selection activity by clicking home page, deletes an accout in the background and comes back to the earlier accout selection activity, the deleted account still exists as an option. This cl fixes this by updating the account list on resume.

Bug: 7135608
Change-Id: Idc9a2fa6451b032310c0ad66f6db0e2f0967feeb