These variables were being used to determine if we should wait for the codec
thead to finish draining. When we needed to wait, we would call
Rendezvous_meet(). However, upon completion of the drain operation the
would always call Rendezvous_force() all the time, so it is safe to call
Rendezvous_meet() all the time without checking the value of decodeDrained.
This renders the variables unnecessary, and they were removed.