[gnome-todo] provider: Add "refresh" vfunc

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 78a15ecd4972c7f8cc21d26f3a9ca08128dddcb4
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Sat Mar 30 20:38:31 2019 -0300

    provider: Add "refresh" vfunc
    
    This is an optional vfunc that forces a refresh
    on the provider.

 src/interfaces/gtd-provider.c | 20 ++++++++++++++++++++
 src/interfaces/gtd-provider.h |  4 ++++
 2 files changed, 24 insertions(+)
---
diff --git a/src/interfaces/gtd-provider.c b/src/interfaces/gtd-provider.c
index 619724a..85d0279 100644
--- a/src/interfaces/gtd-provider.c
+++ b/src/interfaces/gtd-provider.c
@@ -287,6 +287,26 @@ gtd_provider_get_enabled (GtdProvider *provider)
   return GTD_PROVIDER_GET_IFACE (provider)->get_enabled (provider);
 }
 
+/**
+ * gtd_provider_refresh:
+ * @provider: a #GtdProvider
+ *
+ * Asks the provider to refresh. Online providers may want to
+ * synchronize tasks and tasklists, credentials, etc, when this
+ * is called.
+ *
+ * This is an optional feature. Providers that do not implement
+ * the "refresh" vfunc will be ignored.
+ */
+void
+gtd_provider_refresh (GtdProvider *provider)
+{
+  g_return_if_fail (GTD_IS_PROVIDER (provider));
+
+  if (GTD_PROVIDER_GET_IFACE (provider)->refresh)
+    GTD_PROVIDER_GET_IFACE (provider)->refresh (provider);
+}
+
 /**
  * gtd_provider_get_icon:
  * @provider: a #GtdProvider
diff --git a/src/interfaces/gtd-provider.h b/src/interfaces/gtd-provider.h
index 90cf24b..ce77a57 100644
--- a/src/interfaces/gtd-provider.h
+++ b/src/interfaces/gtd-provider.h
@@ -46,6 +46,8 @@ struct _GtdProviderInterface
 
   gboolean           (*get_enabled)                              (GtdProvider        *provider);
 
+  void               (*refresh)                                  (GtdProvider        *provider);
+
   /* Customs */
   GIcon*             (*get_icon)                                 (GtdProvider        *provider);
 
@@ -89,6 +91,8 @@ const gchar*         gtd_provider_get_description                (GtdProvider
 
 gboolean             gtd_provider_get_enabled                    (GtdProvider        *provider);
 
+void                 gtd_provider_refresh                        (GtdProvider        *provider);
+
 GIcon*               gtd_provider_get_icon                       (GtdProvider        *provider);
 
 void                 gtd_provider_create_task                    (GtdProvider        *provider,