movenc: allow override of "writing application" tag

Signed-off-by: Tim Walker <tdskywalker@gmail.com>

CC: libav-stable@libav.org

libavformat/movenc.c

@@ -1858,7 +1858,8 @@ static int mov_write_ilst_tag(AVIOContext *pb, MOVMuxContext *mov,
     mov_write_string_metadata(s, pb, "\251wrt", "composer" , 1);
     mov_write_string_metadata(s, pb, "\251alb", "album"    , 1);
     mov_write_string_metadata(s, pb, "\251day", "date"     , 1);
-    mov_write_string_tag(pb, "\251too", LIBAVFORMAT_IDENT, 0, 1);
+    if (!mov_write_string_metadata(s, pb, "\251too", "encoding_tool", 1))
+        mov_write_string_tag(pb, "\251too", LIBAVFORMAT_IDENT, 0, 1);
     mov_write_string_metadata(s, pb, "\251cmt", "comment"  , 1);
     mov_write_string_metadata(s, pb, "\251gen", "genre"    , 1);
     mov_write_string_metadata(s, pb, "\251cpy", "copyright", 1);