Change the flushing state of all the pads in the collection. No pad
is able to accept anymore data when flushing is TRUE. Calling this
function with flushingFALSE makes pads accept data again.
Caller must ensure that downstream streaming (thread) is not blocked,
e.g. by sending a FLUSH_START downstream.
Change the flushing state of all the pads in the collection. No pad is able to accept anymore data when flushing is TRUE. Calling this function with flushing FALSE makes pads accept data again. Caller must ensure that downstream streaming (thread) is not blocked, e.g. by sending a FLUSH_START downstream.
MT safe.