MenuCommandHandler is not a base class of MenuManager...

... This forces a better placement of state variables in the appropriate
classes.

In future perhaps, MenuManager should be splintered into several classes, one
for each of the main toolbar menus.

src/BatchProcessDialog.cpp

@@ -749,7 +749,7 @@ void MacrosWindow::UpdateMenus()
 {
    // OK even on mac, as dialog is modal.
    auto p = GetActiveProject();
-   GetMenuCommandHandler(*p).RebuildMenuBar(*p);
+   GetMenuManager(*p).RebuildMenuBar(*p);
 }
 
 void MacrosWindow::UpdateDisplay( bool bExpanded )