Improve logging of NSS errors that do not map to network errors.

net/socket/nss_ssl_util.cc

Index: net/socket/nss_ssl_util.cc
diff --git a/net/socket/nss_ssl_util.cc b/net/socket/nss_ssl_util.cc
index 20911d5a67bdb8da8f0fb6d2b89109950a9adb61..4811e46f3934ed701f25b91c08769c2c090485cf 100644
--- a/net/socket/nss_ssl_util.cc
+++ b/net/socket/nss_ssl_util.cc
@@ -357,12 +357,16 @@ int MapNSSError(PRErrorCode err) {
       return ERR_SSL_INAPPROPRIATE_FALLBACK;
 
     default: {
+      const char* pr_error = PR_ErrorToName(err);

[wtc, 2014/03/25 15:29:40]

This variable should be named "err_name" because it is the symbolic name of
|err|.

+      if (pr_error == NULL)
+        pr_error = "";
       if (IS_SSL_ERROR(err)) {
-        LOG(WARNING) << "Unknown SSL error " << err
+        LOG(WARNING) << "Unknown SSL error " << err << " (" << pr_error << ")"
                      << " mapped to net::ERR_SSL_PROTOCOL_ERROR";
         return ERR_SSL_PROTOCOL_ERROR;
       }
-      LOG(WARNING) << "Unknown error " << err << " mapped to net::ERR_FAILED";
+      LOG(WARNING) << "Unknown error " << err << " (" << pr_error << ")"
+                   << " mapped to net::ERR_FAILED";
       return ERR_FAILED;
     }
   }