Options can be incorrectly cached following database errors.

[peterwilsoncc]

Various wpdb methods can return falsey values to indicate one of two things:

• 0: zero effected rows
• false: a database error

In get_option(), get_network_option(), delete_option() and delete_network_option() the results of the database query are imprecisely checked and can result in populated the notoptions cache incorrectly. Either by adding to the cache following a database error, or not adding to the cache when the zero rows are effected while deleting an option.

In add_network_option(), update_network_option() the notoptions cache is cleared prior to the database query without accounting for database errors. (This simply causes additional queries rather than incorrect data being returned.)

Related #61484, props @bjorsch for picking up.