patch 9.1.1351: Return value of getcmdline() inconsistent in CmdlineLeavePre
Problem: Return value of getcmdline() inconsistent in CmdlineLeavePre
when leaving cmdline in different ways (after v9.1.1329).
Solution: Trigger CmdlineLeavePre before calling abandon_cmdline() so
that getcmdline() can return the command line (zeertzjq).