QTableView/TreeView not updated when header size is changed programatically

When the size of a QHeaderView is changed programatically e.g. with setFixedWidth() after the view was layouted, the change is not propagated to the QTableView/TreeView.
See attached testcase to reproduce the issue

/edit: a simple solution would be to fire geometriesChanged() on QEvent::Resize but I'm not sure if this creates to much noise...