Fixed video seeking for strange videos.
Fixed video seeking for strange videos.

svn path=/trunk/libavg/; revision=9194

yyd01245/libavg,scotty007/libavg,scotty007/libavg,libavg/libavg,scotty007/libavg,yyd01245/libavg,hoodie/libavg,libavg/libavg,th3infinity/libavg,th3infinity/libavg,yyd01245/libavg,th3infinity/libavg,th3infinity/libavg,hoodie/libavg,yyd01245/libavg,hoodie/libavg,libavg/libavg,libavg/libavg,scotty007/libavg,hoodie/libavg