tests: set default fps to 30 for .vp8 container
tests: set default fps to 30 for .vp8 container

xuguangxin/libyami,bluceldg/libyami,halleyzhao/libyami,andyLiuChina/libyami,andyLiuChina/libyami,lizhong1008/libyami,bluceldg/libyami,zhaobob/libyami,bluceldg/libyami,yizhouwei/libyami,wlin70/libyami,dspmeng/libyami,clearlylin/libyami,wlin70/libyami,zhaobob/libyami,xuguangxin/libyami,bluceldg/libyami,01org/libyami,seanvk/libyami,wlin70/libyami,dspmeng/libyami,chivakker/libyami,clearlylin/libyami,yizhouwei/libyami,seanvk/libyami,lizhong1008/libyami,uartie/libyami,uartie/libyami,BtbN/libyami,YuJiankang/libyami,stripes416/libyami,chivakker/libyami,YuJiankang/libyami,xuguangxin/libyami,halleyzhao/libyami,zhongcong/libyami,zhongcong/libyami,halleyzhao/libyami,uartie/libyami,BtbN/libyami,zhongcong/libyami,lizhong1008/libyami,zhongcong/libyami,YuJiankang/libyami,zhaobob/libyami,BtbN/libyami,01org/libyami,xuguangxin/libyami,clearlylin/libyami,andyLiuChina/libyami,stripes416/libyami,seanvk/libyami,BtbN/libyami,chivakker/libyami,halleyzhao/libyami,yizhouwei/libyami,dspmeng/libyami,01org/libyami,andyLiuChina/libyami,stripes416/libyami,wlin70/libyami