droidvenc: Don't forget to finish the frame if we fail to process encoded data.
droidvenc: Don't forget to finish the frame if we fail to process encoded data.

We own an extra ref and we must call finish otherwise we leak the data.
In practice an error will be followed by a codec stop so the base class will
clean up after us but it's better if we do the cleanup.

sailfishos/gst-droid,mlehtima/gst-droid,mlehtima/gst-droid