move 8 copies of the same function to common code

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@54092 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/menu.cpp

@@ -625,17 +625,6 @@ wxMenuItem::~wxMenuItem()
    // don't delete menu items, the menus take care of that
 }
 
-// return the menu item text without any menu accels
-/* static */
-
-wxString wxMenuItemBase::GetLabelText(const wxString& text)
-{
-    // The argument to this function will now always be in wxWidgets standard label
-    // format, not GTK+ format, so we do what the other ports do.
-
-    return wxStripMenuCodes(text);
-}
-
 void wxMenuItem::SetItemLabel( const wxString& str )
 {
 #if wxUSE_ACCEL