Actually we have revisions and we use the same declaration for components in UI Toolkit as well. And the revisioning of ViewItems attached properties are also broken, see https://code.launchpad.net/~zsombi/ubuntu-ui-toolkit/listitem-expansion/+merge/254375, where I had to do an ugly workaround to get the revisioned API accepted in Expansion.qml test code.
Actually we have revisions and we use the same declaration for components in UI Toolkit as well. And the revisioning of ViewItems attached properties are also broken, see https:/ /code.launchpad .net/~zsombi/ ubuntu- ui-toolkit/ listitem- expansion/ +merge/ 254375, where I had to do an ugly workaround to get the revisioned API accepted in Expansion.qml test code.