commit e9b00820e5047cbac7ac74874406b06411d8deee
author Edwin Kempin <ekempin@google.com> Thu Feb 23 13:12:53 2023 +0100
committer Edwin Kempin <ekempin@google.com> Thu Feb 23 13:12:53 2023 +0100
tree 5de415540afc456e99f73d74d2e6ce26978264c3
parent 197d756f841d6adc39fec2f0d2cf6b358c15d0e0

AccountResolver.ByEmail: Ignore inconsistent accounts if multiple accounts are matched

An email can only belong to a single account. If multiple accounts are
found for an email it means there is an inconsistency, i.e. some of the
found accounts have a preferred email set that they do not own via an
external ID. In this case we return only the one account that actually
owns the email via an external ID. Returning all matched accounts
instead of only the account that owns the email via an external ID was a
behavior change that was accidentally introduced by change I799bf1c57.

If none of the matched accounts owns the email, we return all matches to
be consistent with the behavior of Emails.getAccountFor(String) that is
used if the user can see secondary emails (Emails.getAccountFor(String)
falls back to searching accounts by preferred email if there is no
account owning the email via an external ID and all of them are
returned).

This fall-back is important for Google since internally we support a
process to link accounts, which creates such inconsistent accounts
(accounts having a preferred email that they do not own via an external
ID).

Release-Notes: skip
Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: Ic0002ef35899a3df8fbc2138f91619326fe38798