Use server features for account muc service

issue #878

src/xmpp/connection.c

@@ -290,6 +290,10 @@ connection_supports(const char *const feature)
 char*
 connection_jid_for_feature(const char *const feature)
 {
+    if (conn.features_by_jid == NULL) {
+        return NULL;
+    }
+
     GList *jids = g_hash_table_get_keys(conn.features_by_jid);
 
     GList *curr = jids;

src/xmpp/connection.h

@@ -54,7 +54,6 @@ void connection_set_disco_items(GSList *items);
 xmpp_conn_t* connection_get_conn(void);
 xmpp_ctx_t* connection_get_ctx(void);
 char *connection_get_domain(void);
-char* connection_jid_for_feature(const char *const feature);
 GHashTable* connection_get_features(const char *const jid);
 
 void connection_clear_data(void);

src/xmpp/xmpp.h

@@ -58,6 +58,7 @@
 #define XMPP_FEATURE_BLOCKING "urn:xmpp:blocking"
 #define XMPP_FEATURE_RECEIPTS "urn:xmpp:receipts"
 #define XMPP_FEATURE_LASTACTIVITY "jabber:iq:last"
+#define XMPP_FEATURE_MUC "http://jabber.org/protocol/muc"
 
 typedef enum {
     JABBER_CONNECTING,
@@ -129,6 +130,7 @@ gboolean connection_is_secured(void);
 gboolean connection_send_stanza(const char *const stanza);
 GList* connection_get_available_resources(void);
 gboolean connection_supports(const char *const feature);
+char* connection_jid_for_feature(const char *const feature);
 
 char* message_send_chat(const char *const barejid, const char *const msg, const char *const oob_url,
     gboolean request_receipt);