[evince] libview: Document is-loading property

[Germán Poo-Caamaño <gpoo src gnome org>]

commit 5c9acd557b9c3630839561e62834362fb860d502
Author: Germán Poo-Caamaño <gpoo gnome org>
Date:   Thu Oct 5 23:28:54 2017 -0300

    libview: Document is-loading property
    
    The property replaced the old EvLoadingWindow.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=693864

 libview/ev-view.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/libview/ev-view.c b/libview/ev-view.c
index f22a0c8..9db54f7 100644
--- a/libview/ev-view.c
+++ b/libview/ev-view.c
@@ -7502,6 +7502,13 @@ ev_view_class_init (EvViewClass *class)
        class->move_cursor = ev_view_move_cursor;
        class->activate = ev_view_activate;
 
+       /**
+        * EvView:is-loading:
+        *
+        * Allows to implement a custom notification system.
+        *
+        * Since: 3.8
+        */
        g_object_class_install_property (object_class,
                                         PROP_IS_LOADING,
                                         g_param_spec_boolean ("is-loading",