Close dangling groups cursor.

app/src/main/java/org/thoughtcrime/securesms/util/IdentityUtil.java

@@ -69,7 +69,8 @@ public class IdentityUtil {
     long          time          = System.currentTimeMillis();
     SmsDatabase   smsDatabase   = DatabaseFactory.getSmsDatabase(context);
     GroupDatabase groupDatabase = DatabaseFactory.getGroupDatabase(context);
-    GroupDatabase.Reader reader        = groupDatabase.getGroups();
+
+    try (GroupDatabase.Reader reader = groupDatabase.getGroups()) {
 
       GroupDatabase.GroupRecord groupRecord;
 
@@ -96,6 +97,7 @@ public class IdentityUtil {
           }
         }
       }
+    }
 
     if (remote) {
       IncomingTextMessage incoming = new IncomingTextMessage(recipient.getId(), 1, time, null, Optional.absent(), 0, false);