[gnome-software] appstream plugin: Add locking to one more place

[Kalev Lember <klember src gnome org>]

commit 23ee17f2bfba1b8a788f53533869a2d0efc62b8d
Author: Kalev Lember <kalevlember gmail com>
Date:   Sat Jun 6 22:55:20 2015 +0200

    appstream plugin: Add locking to one more place
    
    Missed it in the previous commit.

 src/plugins/gs-plugin-appstream.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/plugins/gs-plugin-appstream.c b/src/plugins/gs-plugin-appstream.c
index 441d3dd..608ba42 100644
--- a/src/plugins/gs-plugin-appstream.c
+++ b/src/plugins/gs-plugin-appstream.c
@@ -187,6 +187,8 @@ gs_plugin_startup (GsPlugin *plugin, GError **error)
        guint i;
        _cleanup_hashtable_unref_ GHashTable *origins = NULL;
 
+       g_mutex_lock (&plugin->priv->store_mutex);
+
        /* clear all existing applications if the store was invalidated */
        as_store_remove_all (plugin->priv->store);
 
@@ -247,6 +249,7 @@ gs_plugin_startup (GsPlugin *plugin, GError **error)
                }
        }
 out:
+       g_mutex_unlock (&plugin->priv->store_mutex);
        gs_profile_stop (plugin->profile, "appstream::startup");
        return ret;
 }