add wxUSE_IMAGE checks around ctors using Union() overload only defined when wxUSE_IMAGE==1 (closes #10561)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@59602 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/region.h

@@ -21,6 +21,7 @@ public:
     wxRegion(const wxRect& rect);
     wxRegion(WXHRGN hRegion); // Hangs on to this region
     wxRegion(size_t n, const wxPoint *points, int fillStyle = wxODDEVEN_RULE );
+#if wxUSE_IMAGE
     wxRegion( const wxBitmap& bmp)
     {
         Union(bmp);
@@ -30,6 +31,7 @@ public:
     {
         Union(bmp, transColour, tolerance);
     }
+#endif // wxUSE_IMAGE
 
     virtual ~wxRegion();