This fixes the "No such file or directory" error when invoking
flatpak-validate-icon with the --sandbox argument.

diff --git a/icon-validator/validate-icon.c b/icon-validator/validate-icon.c
index 6c3d152..0d70e55 100644
--- a/icon-validator/validate-icon.c
+++ b/icon-validator/validate-icon.c
@@ -163,7 +163,7 @@ rerun_in_sandbox (const char *arg_width,
                   const char *arg_height,
                   const char *filename)
 {
-  const char * const usrmerged_dirs[] = { "bin", "lib32", "lib64", "lib", "sbin" };
+  const char * const usrmerged_dirs[] = { };
   int i;
   g_autoptr(GPtrArray) args = g_ptr_array_new_with_free_func (g_free);
   char validate_icon[PATH_MAX + 1];
@@ -183,8 +183,7 @@ rerun_in_sandbox (const char *arg_width,
             "--unshare-ipc",
             "--unshare-net",
             "--unshare-pid",
-            "--ro-bind", "/usr", "/usr",
-            "--ro-bind-try", "/etc/ld.so.cache", "/etc/ld.so.cache",
+            "--ro-bind", "@storeDir@", "@storeDir@",
             "--ro-bind", validate_icon, validate_icon,
             NULL);

@@ -227,6 +226,10 @@ rerun_in_sandbox (const char *arg_width,
     add_args (args, "--setenv", "G_MESSAGES_DEBUG", g_getenv ("G_MESSAGES_DEBUG"), NULL);
   if (g_getenv ("G_MESSAGES_PREFIXED"))
     add_args (args, "--setenv", "G_MESSAGES_PREFIXED", g_getenv ("G_MESSAGES_PREFIXED"), NULL);
+  if (g_getenv ("GDK_PIXBUF_MODULE_FILE"))
+    add_args (args, "--setenv", "GDK_PIXBUF_MODULE_FILE", g_getenv ("GDK_PIXBUF_MODULE_FILE"), NULL);
+  if (g_getenv ("XDG_DATA_DIRS"))
+    add_args (args, "--setenv", "XDG_DATA_DIRS", g_getenv ("XDG_DATA_DIRS"), NULL);

   add_args (args, validate_icon, arg_width, arg_height, filename, NULL);
   g_ptr_array_add (args, NULL);