Fixed bug in LuceneChangeIndex.deleteAll()

Change-Id: I5f87b39a7d6159542a95620fe9caecfdeca1f469

gerrit-lucene/src/main/java/com/google/gerrit/lucene/LuceneChangeIndex.java

diff --git a/gerrit-lucene/src/main/java/com/google/gerrit/lucene/LuceneChangeIndex.java b/gerrit-lucene/src/main/java/com/google/gerrit/lucene/LuceneChangeIndex.java
index d352b37..5e8cac5 100644
--- a/gerrit-lucene/src/main/java/com/google/gerrit/lucene/LuceneChangeIndex.java
+++ b/gerrit-lucene/src/main/java/com/google/gerrit/lucene/LuceneChangeIndex.java
@@ -218,6 +218,7 @@
   @Override
   public void deleteAll() throws IOException {
     openIndex.deleteAll();
+    closedIndex.deleteAll();
   }
 
   @Override