This is commit is just the output of running the syntax updater on the
files in the internal/compiler/widgets directory.
No extra manual steps were done.
Note: In order to run the updater, I did a hack so that the updater wouldn't
choke on internal item used by the styles by commenting out the check in
ElementType::lookup_type_for_child_element
Now it's also possible to toggle checked by click on the text of the CheckBox similar to fluent design
GroupBox now respect the minimum width of the title, to avoid elision
Adopt SpinBox: set focus when buttons are clicked #1795 on md SpinBox