SetFrame          893 third_party/libwebp/demux/demux.c   return SetFrame(frame, iter);
SetFrame          898 third_party/libwebp/demux/demux.c   return SetFrame(iter->frame_num + 1, iter);
SetFrame          904 third_party/libwebp/demux/demux.c   return SetFrame(iter->frame_num - 1, iter);