Follow-up to r1663842:
Follow-up to r1663842:

* tools/dist/backport.pl: Unbreak compilation on Perl v5.16 and older.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1664148 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion