[gimp] app: fix drawable-preview offset

[Ell <ell src gnome org>]

commit e6a59eba086211999312fabe4027e60233333027
Author: Ell <ell_se yahoo com>
Date:   Tue Jul 3 00:22:34 2018 -0400

    app: fix drawable-preview offset

 app/widgets/gimpviewrendererdrawable.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/app/widgets/gimpviewrendererdrawable.c b/app/widgets/gimpviewrendererdrawable.c
index d296de984b..157df105ac 100644
--- a/app/widgets/gimpviewrendererdrawable.c
+++ b/app/widgets/gimpviewrendererdrawable.c
@@ -333,8 +333,8 @@ gimp_view_renderer_drawable_render (GimpViewRenderer *renderer,
 
       renderdrawable->priv->render_async  = async;
       renderdrawable->priv->render_widget = g_object_ref (widget);
-      renderdrawable->priv->render_buf_x  = 0;
-      renderdrawable->priv->render_buf_y  = 0;
+      renderdrawable->priv->render_buf_x  = render_buf_x;
+      renderdrawable->priv->render_buf_y  = render_buf_y;
       renderdrawable->priv->render_update = FALSE;
 
       gimp_async_add_callback (