
GerritPublicKeyChecker needs to find the account for a given public PGP key. Lookup the coresponding external ID via the account index instead of loading it from the database. This is a preparation for moving the external IDs into git. Change-Id: Ia456c5bdb89da294b51a86087b92ad14165eae8a Signed-off-by: Edwin Kempin <ekempin@google.com>