About USE_META_KEYBINDING (Stephan?)

[Jean-Marc Lasgouttes]

While investigating ticket #8364, I stumbled on commit e9d943ae, which 
does changes to KeySequence.cpp like:

                        case 'm': case 'M':
+#if defined(USE_MACOSX_PACKAGING) || defined(USE_META_KEYBINDING)
+                               mod |= MetaModifier;
+                               i += 2;
+                               continue;
+#endif
It happens that this USE_META_KEYBINDING macro is not defined anywhere. 
What is the intent here? Only handle Alt and Meta separately? Is this 
documented somewhere?

Why not just define USE_META_KEYBINDING in configure for the mac build?

JMarc