Return nameId email as email address if not otherwise specified

Previously the nameId section of this function would never be used, as
getEmailAddress would just return the null emailAddress regardless of
whether or not the nameId was an email. This corrects that behavior.

Change-Id: Ia68abd5f1806f41a8fadcb86ebe3c413308e430c
diff --git a/src/main/java/com/googlesource/gerrit/plugins/saml/SamlWebFilter.java b/src/main/java/com/googlesource/gerrit/plugins/saml/SamlWebFilter.java
index 8eaf717..06db693 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/saml/SamlWebFilter.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/saml/SamlWebFilter.java
@@ -282,7 +282,7 @@
           "Email address attribute not found, NameId {} does not look like an email.", nameId);
       return null;
     }
-    return emailAddress;
+    return nameId;
   }
 
   private String getUserName(SAML2Profile user) {