[evolution-data-server] Misleading error for Google collection account without Calendar part

[Milan Crha <mcrha src gnome org>]

commit f82a28be92734f81ab58f050f14cbb86dd02f3ac
Author: Milan Crha <mcrha redhat com>
Date:   Wed Sep 20 14:15:59 2017 +0200

    Misleading error for Google collection account without Calendar part
    
    When a Google collection account had not enabled Calendar part,
    a misleading error about failed connection for the account with
    "Unknown error" detailed description could show up. The reason
    was that the Google backend didn't even try to connect, due to
    the disabled Calendar part, but it reported error, even without
    actual error message (hence the "Unknown error" text).

 src/modules/google-backend/module-google-backend.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/src/modules/google-backend/module-google-backend.c 
b/src/modules/google-backend/module-google-backend.c
index c33e869..115c48f 100644
--- a/src/modules/google-backend/module-google-backend.c
+++ b/src/modules/google-backend/module-google-backend.c
@@ -466,6 +466,8 @@ google_backend_authenticate_sync (EBackend *backend,
        if (e_source_collection_get_calendar_enabled (collection_extension) && calendar_url) {
                result = e_webdav_collection_backend_discover_sync (E_WEBDAV_COLLECTION_BACKEND (backend), 
calendar_url, NULL,
                        credentials, out_certificate_pem, out_certificate_errors, cancellable, error);
+       } else {
+               result = E_SOURCE_AUTHENTICATION_ACCEPTED;
        }
 
 #if GDATA_CHECK_VERSION(0,15,1)