D21320: Fix build with poppler < 0.51

[Albert Astals Cid]

aacid added a comment.


  I've reverted the changeset since it was breaking the build

REPOSITORY
  R223 Okular

REVISION DETAIL
  https://phabricator.kde.org/D21320

To: volkov, #okular, sander
Cc: aacid, joaonetto, okular-devel, tfella, ngraham, darcyshen