ChangeScreen2: Fix NPE in /related caused by wrong variable

Change-Id: Iff34707b77b6b579c8441f1826510ac1a56b09b3

gerrit-server/src/main/java/com/google/gerrit/server/change/GetRelated.java

diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/change/GetRelated.java b/gerrit-server/src/main/java/com/google/gerrit/server/change/GetRelated.java
index f0a1738..7f519c9 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/change/GetRelated.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/change/GetRelated.java
@@ -167,7 +167,7 @@
       for (PatchSet.Id psId : children.get(id)) {
         PatchSet.Id e = matches.get(psId.getParentKey());
         if ((e == null || e.get() < psId.get())
-            && isVisible(projectCtl, changes, patchSets, e))  {
+            && isVisible(projectCtl, changes, patchSets, psId))  {
           matches.put(psId.getParentKey(), psId);
         }
       }