Fix crash on Mlt::Animation::is_key
Fix crash on Mlt::Animation::is_key

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