Add log messages to troubleshoot OAuth/OpenID linking

Change-Id: Ic8e13eb570d66e144520c29cd65308ce1f1d15c1
diff --git a/gerrit-oauth/src/main/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java b/gerrit-oauth/src/main/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
index 27a1f57..6e3ea7a 100644
--- a/gerrit-oauth/src/main/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
+++ b/gerrit-oauth/src/main/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
@@ -124,6 +124,7 @@
         if (claimedId != null && actualId != null) {
           if (claimedId.equals(actualId)) {
             // Both link to the same account, that's what we expected.
+            log.debug("OAuth2: claimed identity equals current id");
           } else {
             // This is (for now) a fatal error. There are two records
             // for what might be the same user.
@@ -138,6 +139,8 @@
         } else if (claimedId != null && actualId == null) {
           // Claimed account already exists: link to it.
           //
+          log.info("OAuth2: linking claimed identity to {}",
+              claimedId.toString());
           try {
             accountManager.link(claimedId, areq);
           } catch (OrmException e) {
@@ -148,6 +151,8 @@
             return;
           }
         }
+      } else {
+        log.debug("OAuth2: claimed identity is empty");
       }
       areq.setUserName(user.getUserName());
       areq.setEmailAddress(user.getEmailAddress());
diff --git a/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/OpenIdServiceImpl.java b/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/OpenIdServiceImpl.java
index 1681bc2..44b58c3 100644
--- a/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/OpenIdServiceImpl.java
+++ b/gerrit-openid/src/main/java/com/google/gerrit/httpd/auth/openid/OpenIdServiceImpl.java
@@ -157,6 +157,7 @@
     final AuthRequest aReq;
     try {
       aReq = manager.authenticate(state.discovered, state.retTo.toString());
+      log.debug("OpenID: openid-realm={}", state.contextUrl);
       aReq.setRealm(state.contextUrl);
 
       if (requestRegistration(aReq)) {