Made wxBORDER_THEME the same as wxBORDER_DEFAULT

Moved wxControl::GetBorderStyle into wxWindowMSW::GetBorderStyle
but added GetBorderStyle to have the same behaviour as before (so e.g.
notebook panels don't get borders)
Improved help window borders


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@47963 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/control.h

@@ -72,9 +72,6 @@ public:
     virtual WXDWORD MSWGetStyle(long style, WXDWORD *exstyle) const;
 
 protected:
-    // choose the default border for this window
-    virtual wxBorder GetDefaultBorder() const;
-
     // return default best size (doesn't really make any sense, override this)
     virtual wxSize DoGetBestSize() const;