Add wxOVERRIDE and use it in common and wxOSX code.

Make overriding virtual methods more explicit and enable additional checks
provided by C++11 compilers when "override" is used.

Closes #16100.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76173 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/dbgrptg.cpp

@@ -252,8 +252,8 @@ class wxDebugReportDialog : public wxDialog
 public:
     wxDebugReportDialog(wxDebugReport& dbgrpt);
 
-    virtual bool TransferDataToWindow();
-    virtual bool TransferDataFromWindow();
+    virtual bool TransferDataToWindow() wxOVERRIDE;
+    virtual bool TransferDataFromWindow() wxOVERRIDE;
 
 private:
     void OnView(wxCommandEvent& );