fixed crash on new project

mainwindow.cpp

@@ -361,6 +361,7 @@ void MainWindow::on_actionProject_triggered()
         undo_stack.clear();
         project_url.clear();
         panel_project->new_project();
+        panel_timeline->redraw_all_clips(false);
     }
 }
 

panels/project.cpp

@@ -450,9 +450,9 @@ void Project::clear() {
 
 void Project::new_project() {
     // clear existing project
+    set_sequence(NULL);
     clear();
     project_changed = false;
-    set_sequence(NULL);
 }
 
 QTreeWidgetItem* Project::find_loaded_folder_by_id(int id) {