FlatpakPermission: Add back no-args default constructor
Older toolchain such as Kubuntu requires default constructor to use this class with QVector. Do not use this constructor manually. BUG: 467399 (cherry picked from commit 7e644d8f)
Older toolchain such as Kubuntu requires default constructor to use this class with QVector. Do not use this constructor manually. BUG: 467399 (cherry picked from commit 7e644d8f)