When setting cache corrupted, make sure we don't write broken values to the new cache file. Also log broken virtual size fetches better and support 0 as a generic "some fields" value.
When setting cache corrupted, make sure we don't write broken values to the
new cache file. Also log broken virtual size fetches better and support 0 as
a generic "some fields" value.

damoxc/dovecot,damoxc/dovecot,damoxc/dovecot,damoxc/dovecot,damoxc/dovecot