100L, fix vf_scale, since copy_ref_props now copy w and h, we must update them

Originally committed as revision 24781 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavfilter/vf_scale.c

@@ -153,6 +153,8 @@ static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
 
     outpicref = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
     avfilter_copy_buffer_ref_props(outpicref, picref);
+    outpicref->video->w = outlink->w;
+    outpicref->video->h = outlink->h;
 
     outlink->out_buf = outpicref;