D7750: fix crash when more than one instances of ExtractorCollection are destructed

[Matthieu Gallien]

mgallien added a comment.


  Should I push the fix in its current version ?

REPOSITORY
  R286 KFileMetaData

REVISION DETAIL
  https://phabricator.kde.org/D7750

To: mgallien, #frameworks
Cc: anthonyfieroni