Fix regression in 0dbd50a on unseekable streams.
Fix regression in 0dbd50a on unseekable streams.

mltframework/mlt,siddharudh/mlt,siddharudh/mlt,mltframework/mlt,j-b-m/mlt,siddharudh/mlt,siddharudh/mlt,j-b-m/mlt,mltframework/mlt,j-b-m/mlt,j-b-m/mlt,mltframework/mlt,mltframework/mlt,j-b-m/mlt,j-b-m/mlt,j-b-m/mlt,siddharudh/mlt,mltframework/mlt,siddharudh/mlt,mltframework/mlt,siddharudh/mlt,mltframework/mlt,siddharudh/mlt,siddharudh/mlt,j-b-m/mlt,mltframework/mlt,j-b-m/mlt,j-b-m/mlt,mltframework/mlt