Gui: Prevent whole-object highlight when picked list is enabled

Removed the logic that forced `onTop=1` when `needPickedList()` is true
in View3DInventorSelection. This was causing the entire object to be
highlighted instead of just the selected sub-element when the "Picked
object list" option was enabled.

(cherry picked from commit 4dcef14bd8)

src/Gui/View3DInventorSelection.cpp

@@ -191,10 +191,7 @@ void View3DInventorSelection::checkGroupOnTop(const SelectionChanges& Reason)
     // onTop==2 means on top only if whole object is selected,
     // onTop==3 means on top only if some sub-element is selected
     // onTop==1 means either
-    if (Gui::Selection().needPickedList()) {
-        onTop = 1;
-    }
-    else if (vp->OnTopWhenSelected.getValue()) {
+    if (vp->OnTopWhenSelected.getValue()) {
         onTop = vp->OnTopWhenSelected.getValue();
     }
     else {