CodeOwnersOnPostReview: Abort when illegal state was reached

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I3ec99722fcb546ade0b6dded8d43c5898a83ea6c

java/com/google/gerrit/plugins/codeowners/backend/CodeOwnersOnPostReview.java

diff --git a/java/com/google/gerrit/plugins/codeowners/backend/CodeOwnersOnPostReview.java b/java/com/google/gerrit/plugins/codeowners/backend/CodeOwnersOnPostReview.java
index f53d831..1596e23 100644
--- a/java/com/google/gerrit/plugins/codeowners/backend/CodeOwnersOnPostReview.java
+++ b/java/com/google/gerrit/plugins/codeowners/backend/CodeOwnersOnPostReview.java
@@ -196,6 +196,7 @@
           oldApprovals,
           approvals,
           requiredApproval);
+      return Optional.empty();
     }
 
     if (ownedPaths.size() <= maxPathsInChangeMessage) {