Merge commit '0ddc53da'

* commit '0ddc53da':
  mpegvideo: synchronize AVFrame pointers in ERContext fully

Conflicts:
	libavcodec/mpegvideo.c

See: 8ef9dcf1Merged-by: NMichael Niedermayer <michaelni@gmx.at>

libavcodec/mpegvideo.c

@@ -3231,8 +3231,11 @@ void ff_mpeg_set_erpic(ERPicture *dst, Picture *src)
     int i;
 
     memset(dst, 0, sizeof(*dst));
-    if (!src)
+    if (!src) {
+        dst->f  = NULL;
+        dst->tf = NULL;
         return;
+    }
 
     dst->f = src->f;
     dst->tf = &src->tf;