move Freeze() and Thaw() to wxWindowBase to ensure that they behave consistently (i.e. recursively, as described in the docs) in all ports; removed different duplications of freeze count from derived classes

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@51018 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/os2/window.cpp

@@ -1109,12 +1109,12 @@ void wxWindowOS2::Update()
     ::WinUpdateWindow(GetHwnd());
 } // end of wxWindowOS2::Update
 
-void wxWindowOS2::Freeze()
+void wxWindowOS2::DoFreeze()
 {
    ::WinSendMsg(GetHwnd(), WM_VRNDISABLED, (MPARAM)0, (MPARAM)0);
 } // end of wxWindowOS2::Freeze
 
-void wxWindowOS2::Thaw()
+void wxWindowOS2::DoThaw()
 {
    ::WinSendMsg(GetHwnd(), WM_VRNENABLED, (MPARAM)TRUE, (MPARAM)0);