patch 7.4.1903
Problem:    When writing viminfo merging current history with history in
            viminfo may drop recent history entries.
Solution:   Add new format for viminfo lines, use it for history entries.  Use
            a timestamp for ordering the entries. Add test_settime().
            Add the viminfo version.  Does not do merging on timestamp yet.
diff --git a/src/proto/ex_cmds.pro b/src/proto/ex_cmds.pro
index d22b3dd..3057a93 100644
--- a/src/proto/ex_cmds.pro
+++ b/src/proto/ex_cmds.pro
@@ -16,6 +16,7 @@
 int viminfo_readline(vir_T *virp);
 char_u *viminfo_readstring(vir_T *virp, int off, int convert);
 void viminfo_writestring(FILE *fd, char_u *p);
+int barline_writestring(FILE *fd, char_u *s, int remaining_start);
 void do_fixdel(exarg_T *eap);
 void print_line_no_prefix(linenr_T lnum, int use_number, int list);
 void print_line(linenr_T lnum, int use_number, int list);