Xcode 11 doesn't support anything below iOS 7.0 (the linker will automatically
change the deployment target to 7.0), so we need to drop support as well
(since our native bits will be targetting iOS 7.0, and we can't change that).
https://github.com/xamarin/xamarin-macios/issues/6213
This is a static selector that needs to be overridden, which is not the
usual pattern in C#. We re-define it using [New] on subclasses.
Unit tests added for all NSDimension subclasses.
reference:
https://bugzilla.xamarin.com/show_bug.cgi?id=43444
Rolf Bjarne Kvinge
Manuel de la Pena
Sebastien Pouliot
Vincent Dondain