OutgoingEmail: use consistently va.smtpRcptTo reference

All remaining parameters that are passed to validation are used
consistently but not this one.

Change-Id: Ib7ae35b3f0afd3aa9e3f06e231ee498c34f398b7
diff --git a/java/com/google/gerrit/server/mail/send/OutgoingEmail.java b/java/com/google/gerrit/server/mail/send/OutgoingEmail.java
index c1bef07..400bc4f 100644
--- a/java/com/google/gerrit/server/mail/send/OutgoingEmail.java
+++ b/java/com/google/gerrit/server/mail/send/OutgoingEmail.java
@@ -204,12 +204,12 @@
         }
       }
 
-      Set<Address> intersection = Sets.intersection(smtpRcptTo, smtpRcptToPlaintextOnly);
+      Set<Address> intersection = Sets.intersection(va.smtpRcptTo, smtpRcptToPlaintextOnly);
       if (!intersection.isEmpty()) {
         logger.atSevere().log("Email '%s' will be sent twice to %s", messageClass, intersection);
       }
 
-      if (!smtpRcptTo.isEmpty()) {
+      if (!va.smtpRcptTo.isEmpty()) {
         // Send multipart message
         logger.atFine().log("Sending multipart '%s'", messageClass);
         args.emailSender.send(va.smtpFromAddress, va.smtpRcptTo, va.headers, va.body, va.htmlBody);