Piotr Wójcik authored Jun 28, 2019 and Michael Reeves committed Jun 28, 2019

Summary:
Fix filter so files can be actually listed and opened from file dialog.
On occasion, make filter translatable.

Test Plan: Run `kdiff3`, click "File…" button, try to select any file in dialog.

Reviewers: mreeves

Reviewed By: mreeves
This issue does not seem to impact my test machine but the change causes no problems.


Differential Revision: https://phabricator.kde.org/D21885