Avoid visiting elements multiple times in Graph.ParentsIterator

Graph.ParentsIterator visits duplicates. This can even lead to an
infinite iteration if there are cycles. With this change, we ensure that
we never visit any duplicates.

Change-Id: I79c6201f0c5fe0345752788583f7fb6d3b088305
Signed-off-by: Philip Langer <planger@eclipsesource.com>
1 file changed