[gtk+] css: Handle image loading errors graciously

[Matthias Clasen <matthiasc src gnome org>]

commit 419f2c670dcfe7975bb31970991d844f5e38c74e
Author: Matthias Clasen <mclasen redhat com>
Date:   Thu Jan 21 08:18:46 2016 -0500

    css: Handle image loading errors graciously
    
    If we fail to load the image for a -gtk-recolor() expression,
    fall back to using the image-missing icon instead of crashing,
    and include more details in the warning message.

 gtk/gtkcssimagerecolor.c |   14 +++++++++++---
 1 files changed, 11 insertions(+), 3 deletions(-)
---
diff --git a/gtk/gtkcssimagerecolor.c b/gtk/gtkcssimagerecolor.c
index 0d6948a..306e7ab 100644
--- a/gtk/gtkcssimagerecolor.c
+++ b/gtk/gtkcssimagerecolor.c
@@ -108,17 +108,25 @@ gtk_css_image_recolor_load (GtkCssImageRecolor *recolor,
   GdkRGBA fg, success, warning, error;
   GdkPixbuf *pixbuf;
   GtkCssImage *image;
+  GError *gerror = NULL;
 
   lookup_symbolic_colors (style, palette, &fg, &success, &warning, &error);
 
   info = gtk_icon_info_new_for_file (url->file, 0, 1);
-  pixbuf = gtk_icon_info_load_symbolic (info, &fg, &success, &warning, &error, NULL, NULL);
+  pixbuf = gtk_icon_info_load_symbolic (info, &fg, &success, &warning, &error, NULL, &gerror);
   g_object_unref (info);
 
   if (pixbuf == NULL)
     {
-      g_warning ("Failed to load icon");
-      return NULL;
+      char *uri;
+
+      /* XXX: Get the error somehow back to the CssProvider */
+      uri = g_file_get_uri (url->file);
+      g_warning ("Error loading image '%s': %s\n", uri, gerror->message);
+      g_error_free (gerror);
+      g_free (uri);
+
+      pixbuf = gtk_icon_theme_load_icon (gtk_icon_theme_get_default (), "image-missing", 24, 0, NULL);
     }
 
   image = _gtk_css_image_surface_new_for_pixbuf (pixbuf);