[mutter] monitor-config-store: Replace key when replacing config

[Jonas Ådahl <jadahl src gnome org>]

commit 0608ae2d4e8e69a7dbfa92f5e5313da8b7a6197b
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Apr 13 13:03:12 2017 +0800

    monitor-config-store: Replace key when replacing config
    
    g_hash_table_insert() doesn't replace the key. This was a problem
    because the key was owned by the value inserted into the hash table, so
    when a value was removed, the key was freed, meaning that the key in
    the hash table was no pointing to freed memory. Fix this by using
    g_hash_table_replace() instead, which work the same except that it
    replaces the key with the one passed. This means that the key of a
    value in the hash table is always the key owned by the value.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=777732

 src/backends/meta-monitor-config-store.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/backends/meta-monitor-config-store.c b/src/backends/meta-monitor-config-store.c
index 7c4c624..aa7f08a 100644
--- a/src/backends/meta-monitor-config-store.c
+++ b/src/backends/meta-monitor-config-store.c
@@ -1185,8 +1185,8 @@ void
 meta_monitor_config_store_add (MetaMonitorConfigStore *config_store,
                                MetaMonitorsConfig     *config)
 {
-  g_hash_table_insert (config_store->configs,
-                       config->key, g_object_ref (config));
+  g_hash_table_replace (config_store->configs,
+                        config->key, g_object_ref (config));
 
   if (!config_store->custom_file)
     meta_monitor_config_store_save (config_store);