Remove all references to Self in relation to navigate.

After this change, Self should only be used in the context of
relationTo().

Change-Id: I04bb2bf7c480f9350aceb6e53d78e5cf1808d53e
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@nokia.com>

src/gui/accessible/qaccessibleobject.cpp

@@ -262,9 +262,6 @@ int QAccessibleApplication::navigate(QAccessible::RelationFlag relation, int,
     QObject *targetObject = 0;
 
     switch (relation) {
-    case QAccessible::Self:
-        targetObject = object();
-        break;
     case QAccessible::FocusChild:
         if (QWindow *window = QGuiApplication::activeWindow()) {
             *target = window->accessibleRoot();