Handle invalid PhoneAccountHandle for CarrierIdentifier

Previously the phoneAccountHandle is validated before creating the CarrierIdentifier, but it seems like there's a chance that it would be invalidated in the gap before the identifier is created.

TEST=TAP
Bug: 73890027
Test: TAP
PiperOrigin-RevId: 197172168
Change-Id: I6f4f77819ed6ce9f3449f7e47a3538af1098d826
2 files changed