* tools/dist/backport.pl
  (main): Trap the r1461405 failure mode.
    In r1461405, @lines contained two entries because the blank line
    between them contained whitespace, which Perl's paragraph mode
    does not recognise as a paragraph separator.

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1461798 13f79535-47bb-0310-9956-ffa450edef68