Reland "Check transport before registering."

This reverts commit eff97a8123278dcb42936f97a91e9ffff783ef63.

Reason for revert: relanding once manifests have been fixed.
Bug: 139274536
Test: boot emulator (that was failing before)
    no failed registrations
Test: passes boot health check on P1, P2, P3, P3a

Change-Id: Ie39c616298a7e9d14903019299cccdba194e872c
1 file changed