D19533: Don't crash on malformed syntax highlighting files

[Dāvis Mosāns]

davispuh added reviewers: cullmann, dhaumann.

REPOSITORY
  R39 KTextEditor

REVISION DETAIL
  https://phabricator.kde.org/D19533

To: davispuh, cullmann, dhaumann
Cc: kwrite-devel, kde-frameworks-devel, domson, michaelh, ngraham, bruns, 
demsking, cullmann, sars, dhaumann