because the adaptors are parented to the application instance for object
registration purpose the global static deleter double-deletes them
Signed-off-by: Ivailo Monev <xakepa10@gmail.com>
KJob-derived class (custom ones, not those from KIO) are likely to not
have much to work with so that is for the worst case scenario
Signed-off-by: Ivailo Monev <xakepa10@gmail.com>