Remove unneeded dynamic cast in wxPropertyGrid.

It's completely useless to check that an object is of its own statically
declared type as this is always true, simply don't do it.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@71623 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/propgrid/editors.cpp

@@ -732,9 +732,6 @@ void wxPropertyGrid::OnComboItemPaint( const wxPGComboBox* pCb,
                                        wxRect& rect,
                                        int flags )
 {
-    // Sanity check
-    wxASSERT( IsKindOf(CLASSINFO(wxPropertyGrid)) );
-
     wxPGProperty* p = GetSelection();
     wxString text;