[gnome-software] Do not use gtk_icon_theme_load_icon() as it's not thread safe

[Richard Hughes <rhughes src gnome org>]

commit 6a3215403d04cfc99efbb5e04c8e84670d012342
Author: Richard Hughes <richard hughsie com>
Date:   Fri Feb 28 14:57:53 2014 +0000

    Do not use gtk_icon_theme_load_icon() as it's not thread safe
    
    Resolves: https://bugzilla.gnome.org/show_bug.cgi?id=723701

 src/gs-utils.c |   81 +++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 files changed, 75 insertions(+), 6 deletions(-)
---
diff --git a/src/gs-utils.c b/src/gs-utils.c
index aba511f..a353e0d 100644
--- a/src/gs-utils.c
+++ b/src/gs-utils.c
@@ -248,12 +248,74 @@ gs_mkdir_parent (const gchar *path, GError **error)
 }
 
 /**
+ * gs_pixbuf_find_icon_name:
+ */
+static gchar *
+gs_pixbuf_find_icon_name (const gchar *icon_name)
+{
+       guint i, j, k, l;
+       gchar *path;
+       gchar **icons = NULL;
+       const gchar *iconset[] = { "gnome",
+                                  "hicolor",
+                                  NULL };
+       const gchar *sizes[] = { "64x64",
+                                "128x128",
+                                "256x256",
+                                "scalable",
+                                "32x32",
+                                "48x48",
+                                NULL };
+       const gchar *section[] = { "apps",
+                                  "mimetypes",
+                                  "stock",
+                                  "actions",
+                                  "categories",
+                                  "devices",
+                                  "places",
+                                  "status",
+                                  "filesystems",
+                                  "intl",
+                                  "emotes",
+                                  "emblems",
+                                  NULL };
+       const gchar *extentions[] = { "png",
+                                     "svg",
+                                     NULL };
+
+       icons = g_new0 (gchar *, G_N_ELEMENTS (extentions) + 1);
+       for (l = 0; extentions[l] != NULL; l++) {
+               icons[l] = g_strdup_printf ("%s.%s", icon_name, extentions[l]);
+               for (i = 0; iconset[i] != NULL; i++) {
+                       for (j = 0; sizes[j] != NULL; j++) {
+                               for (k = 0; section[k] != NULL; k++) {
+                                       path = g_build_filename ("/usr/share/icons/",
+                                                                iconset[i],
+                                                                sizes[j],
+                                                                section[k],
+                                                                icons[l],
+                                                                NULL);
+                                       if (g_file_test (path, G_FILE_TEST_EXISTS))
+                                               goto out;
+                                       g_free (path);
+                               }
+                       }
+               }
+       }
+       path = NULL;
+out:
+       g_strfreev (icons);
+       return path;
+}
+
+/**
  * gs_pixbuf_load:
  **/
 GdkPixbuf *
 gs_pixbuf_load (const gchar *icon_name, guint icon_size, GError **error)
 {
        GdkPixbuf *pixbuf = NULL;
+       gchar *filename;
 
        g_return_val_if_fail (icon_name != NULL, NULL);
        g_return_val_if_fail (icon_size > 0, NULL);
@@ -269,12 +331,19 @@ gs_pixbuf_load (const gchar *icon_name, guint icon_size, GError **error)
                                                           icon_size,
                                                           error);
        } else if (g_strstr_len (icon_name, -1, ".") == NULL) {
-               pixbuf = gtk_icon_theme_load_icon (gtk_icon_theme_get_default (),
-                                                  icon_name,
-                                                  icon_size,
-                                                  GTK_ICON_LOOKUP_USE_BUILTIN |
-                                                  GTK_ICON_LOOKUP_FORCE_SIZE,
-                                                  error);
+               filename = gs_pixbuf_find_icon_name (icon_name);
+               if (filename != NULL) {
+                       pixbuf = gdk_pixbuf_new_from_file_at_size (filename,
+                                                                  icon_size,
+                                                                  icon_size,
+                                                                  error);
+                       g_free (filename);
+               } else {
+                       g_set_error (error,
+                                    GS_PLUGIN_ERROR,
+                                    GS_PLUGIN_ERROR_FAILED,
+                                    "Cannot find %s", icon_name);
+               }
        } else {
                g_set_error (error,
                             GS_PLUGIN_ERROR,