Original commit message from CVS:
Patch by: Ole André Vadla Ravnås <ole.andre.ravnas at tandberg com>
* sys/dshowsrcwrapper/gstdshowvideosrc.c: (PROP_DEVICE_NAME),
(gst_dshowvideosrc_class_init), (gst_dshowvideosrc_init),
(gst_dshowvideosrc_dispose), (gst_dshowvideosrc_stop),
(gst_dshowvideosrc_unlock), (gst_dshowvideosrc_unlock_stop),
(gst_dshowvideosrc_create), (gst_dshowvideosrc_push_buffer):
* sys/dshowsrcwrapper/gstdshowvideosrc.h:
Don't increase latency by queuing buffers in an async queue when
the streaming thread can't keep up or isn't scheduled often
enough for some other reason, but just drop the previous buffer
in that case. Also implement GstBaseSrc::unlock for faster
unlocking when shutting down. (#520892).
53e5f028ec