ensure that default_get_buffer() doesnt reuse images if the dimension or pix_fmt changed fixes heap overflow, possibly exploitable
ensure that default_get_buffer() doesnt reuse images if the dimension or
pix_fmt changed
fixes heap overflow, possibly exploitable


git-svn-id: a4d7c1866f8397a4106e0b57fc4fbf792bbdaaaf@10064 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

prajnashi/ffmpeg,prajnashi/ffmpeg,prajnashi/ffmpeg,prajnashi/ffmpeg