[evolution-data-server] Prefix password lookup errors, thus they make more sense in UI

[Milan Crha <mcrha src gnome org>]

commit 77ea9422f52601cdd3df6ef915d771721548731f
Author: Milan Crha <mcrha redhat com>
Date:   Thu Aug 6 10:38:40 2015 +0200

    Prefix password lookup errors, thus they make more sense in UI

 libebackend/e-server-side-source.c                 |    2 ++
 .../gnome-online-accounts/e-goa-password-based.c   |    3 +++
 2 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/libebackend/e-server-side-source.c b/libebackend/e-server-side-source.c
index 36a038b..62b55eb 100644
--- a/libebackend/e-server-side-source.c
+++ b/libebackend/e-server-side-source.c
@@ -463,6 +463,8 @@ server_side_source_credentials_lookup_cb (GObject *source_object,
                        fflush (stdout);
                }
 
+               g_prefix_error (&error, "%s", _("Failed to lookup credentials: "));
+
                if (server_side_source_credentials_reason_from_text (data->arg_reason) == 
E_SOURCE_CREDENTIALS_REASON_REQUIRED &&
                    error && !e_source_credentials_provider_can_prompt (E_SOURCE_CREDENTIALS_PROVIDER 
(source_object), E_SOURCE (data->source))) {
                        GEnumClass *enum_class;
diff --git a/modules/gnome-online-accounts/e-goa-password-based.c 
b/modules/gnome-online-accounts/e-goa-password-based.c
index 677cecb..dea674a 100644
--- a/modules/gnome-online-accounts/e-goa-password-based.c
+++ b/modules/gnome-online-accounts/e-goa-password-based.c
@@ -269,6 +269,9 @@ e_goa_password_based_lookup_sync (ESourceCredentialsProviderImpl *provider_impl,
 
        e_util_safe_free_string (password);
 
+       if (!success)
+               g_prefix_error (error, "%s", _("Failed to get password from GOA: "));
+
        return success;
 }