[gtk+] Remove opacity-groups

[Matthias Clasen <matthiasc src gnome org>]

commit 5bdfdcadfffaaed24cead56ea31df9095ad536fa
Author: Alexander Larsson <alexl redhat com>
Date:   Thu Jul 4 11:41:00 2013 +0000

    Remove opacity-groups
    
    GtkWidget had a hack where if opacity is 0.999 we set up an opacity group when
    rendering the widget. This is no longer needed in 3.10, and GtkStack doesn't
    use it anymore.
    
    GdStack is using it, so applications should be ported from GdStack to GtkStack
    in 3.12.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=703603

 gtk/gtkwidget.c |   31 -------------------------------
 1 files changed, 0 insertions(+), 31 deletions(-)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 9adf3e4..1f05c8b 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -460,8 +460,6 @@ struct _GtkWidgetPrivate
   /* SizeGroup related flags */
   guint have_size_groups      : 1;
 
-  guint opacity_group         : 1;
-
   guint8 alpha;
   guint8 user_alpha;
 
@@ -6584,7 +6582,6 @@ _gtk_widget_draw (GtkWidget *widget,
   cairo_save (cr);
 
   push_group =
-    widget->priv->opacity_group ||
     (widget->priv->alpha != 255 &&
      !gtk_widget_is_toplevel (widget));
 
@@ -14986,27 +14983,6 @@ gtk_widget_update_alpha (GtkWidget *widget)
     }
 }
 
-static void
-gtk_widget_set_has_opacity_group  (GtkWidget *widget,
-                                  gboolean has_opacity_group)
-{
-  GtkWidgetPrivate *priv;
-
-  g_return_if_fail (GTK_IS_WIDGET (widget));
-
-  priv = widget->priv;
-
-  has_opacity_group = !!has_opacity_group;
-
-  if (priv->opacity_group == has_opacity_group)
-    return;
-
-  priv->opacity_group = has_opacity_group;
-
-  if (gtk_widget_get_realized (widget))
-    gtk_widget_queue_draw (widget);
-}
-
 /**
  * gtk_widget_set_opacity:
  * @widget: a #GtkWidget
@@ -15044,13 +15020,6 @@ gtk_widget_set_opacity  (GtkWidget *widget,
 
   alpha = round (opacity * 255);
 
-  /* As a kind of hack for internal use we treat an alpha very
-     close to 1.0 (rounds to 255) but not 1.0 as specifying that
-     we want the opacity group behaviour wrt draw handling, but
-     not actually an alpha value. See bug #687842 for discussions. */
-  gtk_widget_set_has_opacity_group (widget,
-                                   alpha == 255 && opacity != 1.0);
-
   if (alpha == priv->user_alpha)
     return;