Invokes the default query handler for the given pad.
The query is sent to all pads internally linked to @pad. Note that
if there are many possible sink pads that are internally linked to
@pad, only one will be sent the query.
Multi-sinkpad elements should implement custom query handlers.
Invokes the default query handler for the given pad. The query is sent to all pads internally linked to @pad. Note that if there are many possible sink pads that are internally linked to @pad, only one will be sent the query. Multi-sinkpad elements should implement custom query handlers.