Added support for using OS X' full screen API (available since OS X 10.7).

Added EnableFullScreenView() to have a full screen button in the title bar and also allowing ShowFullScreen() to make use of the newer full screen API.

See #14357.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76495 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Added default parameter to EnableCloseButton().

Previously the default parameter was only available in wxMSW and wxGTK. Added it to the base class as well to allow EnableCloseButton() calls without a parameter under other platforms too.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76496 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775