libtracker-sparql: Avoid implicitly relying on hashtable iteration order

Recent GLib changed the hashtable hashing, thus changing the order in which
the contents are iterated by a GHashTableIter. Avoid doing that in the one
place we used to (also used to happen in previous vala code).

src/libtracker-data/tracker-sparql.c

@@ -2910,9 +2910,13 @@ translate_InsertClause (TrackerSparql  *sparql,
 	 * Clause may start with:
 	 * 'INSERT' ('OR' 'REPLACE')? ('SILENT')? ('INTO' iri)?
 	 */
-	sparql->current_state.blank_node_map =
-		g_hash_table_new_full (g_str_hash, g_str_equal,
-		                       g_free, g_free);
+	if (sparql->blank_nodes) {
+		g_variant_builder_open (sparql->blank_nodes, G_VARIANT_TYPE ("a{ss}"));
+		sparql->current_state.blank_node_map =
+			g_hash_table_new_full (g_str_hash, g_str_equal,
+					       g_free, g_free);
+	}
+
 	old_graph = sparql->current_state.graph;
 
 	sparql->current_state.type = TRACKER_SPARQL_TYPE_INSERT;
@@ -2939,15 +2943,6 @@ translate_InsertClause (TrackerSparql  *sparql,
 	sparql->current_state.graph = old_graph;
 
 	if (sparql->blank_nodes) {
-		GHashTableIter iter;
-		gpointer key, value;
-
-		g_hash_table_iter_init (&iter, sparql->current_state.blank_node_map);
-		g_variant_builder_open (sparql->blank_nodes, G_VARIANT_TYPE ("a{ss}"));
-
-		while (g_hash_table_iter_next (&iter, &key, &value))
-			g_variant_builder_add (sparql->blank_nodes, "{ss}", key, value);
-
 		g_variant_builder_close (sparql->blank_nodes);
 	}
 
@@ -6174,6 +6169,7 @@ translate_BlankNode (TrackerSparql  *sparql,
 				        bnode_id = tracker_data_query_unused_uuid (sparql->data_manager, iface);
 				        g_hash_table_insert (sparql->current_state.blank_node_map,
 				                             g_strdup (str), bnode_id);
+					g_variant_builder_add (sparql->blank_nodes, "{ss}", str, bnode_id);
 			        }
 
 			        tracker_token_literal_init (sparql->current_state.token, bnode_id);