[gnome-shell] shell: Shut up a compiler warning

[Florian Müllner <fmuellner src gnome org>]

commit 625a38f60575cb30678e6cfbbb9af78d03d96d83
Author: Florian Müllner <fmuellner gnome org>
Date:   Sun Feb 15 10:17:12 2015 +0100

    shell: Shut up a compiler warning

 src/shell-generic-container.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/shell-generic-container.c b/src/shell-generic-container.c
index 7bca9c7..fbeeae9 100644
--- a/src/shell-generic-container.c
+++ b/src/shell-generic-container.c
@@ -225,7 +225,7 @@ shell_generic_container_set_skip_paint (ShellGenericContainer  *self,
   gboolean currently_skipping;
 
   currently_skipping = g_hash_table_lookup (self->priv->skip_paint, child) != NULL;
-  if (!!skip == currently_skipping)
+  if ((!!skip) == currently_skipping)
     return;
 
   if (!skip)