[mutter] meta-background: Add a function to refresh all background instances

[Rui Matos <rtcm src gnome org>]

commit 7c5fe42835ea303a44a837646cfb8f7e1a72e681
Author: Rui Matos <tiagomatos gmail com>
Date:   Thu Mar 19 14:58:25 2015 +0100

    meta-background: Add a function to refresh all background instances
    
    We need to reload the FBOs under some circumstances, this adds a way
    to easily do so.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=739178

 src/compositor/meta-background.c |   14 ++++++++++++++
 src/meta/meta-background.h       |    2 ++
 2 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/src/compositor/meta-background.c b/src/compositor/meta-background.c
index 6284a7a..3f2e23f 100644
--- a/src/compositor/meta-background.c
+++ b/src/compositor/meta-background.c
@@ -71,6 +71,8 @@ enum
 
 G_DEFINE_TYPE (MetaBackground, meta_background, G_TYPE_OBJECT)
 
+static GSList *all_backgrounds = NULL;
+
 static void
 free_fbos (MetaBackground *self)
 {
@@ -305,6 +307,8 @@ meta_background_dispose (GObject *object)
 static void
 meta_background_finalize (GObject *object)
 {
+  all_backgrounds = g_slist_remove (all_backgrounds, object);
+
   G_OBJECT_CLASS (meta_background_parent_class)->finalize (object);
 }
 
@@ -347,6 +351,7 @@ meta_background_init (MetaBackground *self)
   self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self,
                                             META_TYPE_BACKGROUND,
                                             MetaBackgroundPrivate);
+  all_backgrounds = g_slist_prepend (all_backgrounds, self);
 }
 
 static void
@@ -913,3 +918,12 @@ meta_background_set_blend (MetaBackground          *self,
   free_wallpaper_texture (self);
   mark_changed (self);
 }
+
+void
+meta_background_refresh_all (void)
+{
+  GSList *l;
+
+  for (l = all_backgrounds; l; l = l->next)
+    mark_changed (l->data);
+}
diff --git a/src/meta/meta-background.h b/src/meta/meta-background.h
index 822d27b..d48d966 100644
--- a/src/meta/meta-background.h
+++ b/src/meta/meta-background.h
@@ -57,6 +57,8 @@ struct _MetaBackground
   MetaBackgroundPrivate *priv;
 };
 
+void meta_background_refresh_all (void);
+
 GType meta_background_get_type (void);
 
 MetaBackground *meta_background_new  (MetaScreen *screen);