[gtk/gtk-3-22: 1/2] gtkstylecontext: guard against gtk_css_widget_node_get_widget() returning NULL in more places

[Benjamin Otte <otte src gnome org>]

commit d65a4c2e0abeefb1e61e32a2da2c1e1ba9987817
Author: Christoph Reiter <creiter src gnome org>
Date:   Mon Mar 19 18:21:25 2018 +0100

    gtkstylecontext: guard against gtk_css_widget_node_get_widget() returning NULL in more places
    
    When the widget gets finalized it clears the widgetnode and gtk_css_widget_node_get_widget
    returns NULL. Guard against gtk_css_widget_node_get_widget() returning NULL like in other
    places.
    
    See https://gitlab.gnome.org/GNOME/pygobject/issues/28#note_82862

 gtk/gtkstylecontext.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkstylecontext.c b/gtk/gtkstylecontext.c
index 4ef6d574d6..2606815cb3 100644
--- a/gtk/gtkstylecontext.c
+++ b/gtk/gtkstylecontext.c
@@ -187,7 +187,11 @@ gtk_style_context_real_changed (GtkStyleContext *context)
   GtkStyleContextPrivate *priv = context->priv;
 
   if (GTK_IS_CSS_WIDGET_NODE (priv->cssnode))
-    _gtk_widget_style_context_invalidated (gtk_css_widget_node_get_widget (GTK_CSS_WIDGET_NODE 
(priv->cssnode)));
+    {
+      GtkWidget *widget = gtk_css_widget_node_get_widget (GTK_CSS_WIDGET_NODE (priv->cssnode));
+      if (widget != NULL)
+        _gtk_widget_style_context_invalidated (widget);
+    }
 }
 
 static void
@@ -522,7 +526,8 @@ gtk_style_context_push_state (GtkStyleContext *context,
     {
       GtkWidget *widget = gtk_css_widget_node_get_widget (GTK_CSS_WIDGET_NODE (root));
       g_debug ("State %u for %s %p doesn't match state %u set via gtk_style_context_set_state ()",
-               state, gtk_widget_get_name (widget), widget, gtk_css_node_get_state (priv->cssnode));
+               state, (widget == NULL) ? "(null)" : gtk_widget_get_name (widget),
+               widget, gtk_css_node_get_state (priv->cssnode));
     }
   else
     {