Regression in attached enum handling

agent:2020/01/30 14:33:18 build.go:220: PASS   : tst_controls::Material::DialogButtonBox::initTestCase()
agent:2020/01/30 14:33:18 build.go:220: QWARN  : tst_controls::Material::DialogButtonBox::test_attached() QObject::connect: No such signal QQmlObjectModel::itemPooled(int, QObject *) in items/qquickitemview.cpp:237
agent:2020/01/30 14:33:18 build.go:220: QWARN  : tst_controls::Material::DialogButtonBox::test_attached() QObject::connect: No such signal QQmlObjectModel::itemReused(int, QObject *) in items/qquickitemview.cpp:238
agent:2020/01/30 14:33:18 build.go:220: FAIL!  : tst_controls::Material::DialogButtonBox::test_attached() Compared values are not the same
agent:2020/01/30 14:33:18 build.go:220:    Actual   (): [object Object]
agent:2020/01/30 14:33:18 build.go:220:    Expected (): 0
agent:2020/01/30 14:33:18 build.go:220:    Loc: [/home/qt/work/qt/qtquickcontrols2/tests/auto/controls/data/tst_dialogbuttonbox.qml(133)]
[...]
agent:2020/01/30 14:33:18 build.go:220: FAIL!  : tst_controls::Material::DialogButtonBox::test_buttonLayout(WinLayout) Compared values are not the same
agent:2020/01/30 14:33:18 build.go:220:    Actual   (): [object Object]
agent:2020/01/30 14:33:18 build.go:220:    Expected (): 0
agent:2020/01/30 14:33:18 build.go:220:    Loc: [/home/qt/work/qt/qtquickcontrols2/tests/auto/controls/data/tst_dialogbuttonbox.qml(217)]

[...] controls/data/tst_dialogbuttonbox.qml:370:45: Cannot assign primitives to lists 
 agent:2020/02/10 08:23:15 build.go:220:                      DialogButtonBox.buttonRole: DialogButtonBox.AcceptRole? 
 agent:2020/02/10 08:23:15 build.go:220:                                                  ^
 agent:2020/02/10 08:23:15 build.go:220: jom: C:\Users\qt\work\qt\qtquickcontrols2\tests\auto\controls\default\Makefile.Release [check] Error 1
 agent:2020/02/10 08:23:15 build.go:220: jom: C:\Users\qt\work\qt\qtquickcontrols2\tests\auto\controls\default\Makefile [release-check] Error 2
 agent:2020/02/10 08:23:15 build.go:253: Process finished with error: exit status 2