Fix issue in Qt 5.7
Summary:
qml parser doesn't like having namespaced object types in the declaration
of a property. Use QtObject instead.
BUG: 380435
Test Plan:
Tests pass, applied it on my neon machine (sudo vim /usr...) and
it seemed to work
Reviewers: Kirigami, jriddell, davidedmundson
Reviewed By: davidedmundson
Subscribers: plasma-devel
Tags: Kirigami
Differential Revision: https://phabricator.kde.org/D6065