Fix build with Qt 5.11 (missing headers)
Reviewers: #calligra:_3.0, anthonyfieroni, danders
Reviewed By: #calligra:_3.0, anthonyfieroni, danders
Subscribers: anthonyfieroni, danders
Tags: #calligra:_3.0
Differential Revision: https://phabricator.kde.org/D11454