Added wxTLW::SetShape and implementations for wxGTK, wxMSW and an

empty stub for wxMac.
Added some generic helpers and a new ctor to wxRegion.
Added samples/shaped.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@19857 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/mac/toplevel.h

@@ -58,6 +58,8 @@ public:
     virtual void SetIcons(const wxIconBundle& icons) { SetIcon( icons.GetIcon( -1 ) ); }
     virtual void Restore();
 
+    virtual bool SetShape(const wxRegion& region);
+
     virtual bool ShowFullScreen(bool WXUNUSED(show), long WXUNUSED(style) = wxFULLSCREEN_ALL)
     { return FALSE; }
     virtual bool IsFullScreen() const { return FALSE; }