### Godot version

4.1.beta (7b1387ff2)

### System information

Mageia 9, Linux

### Issue description

When opening an empty project in latest `master`, I get these errors:
```
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: get_scene_path (editor/scu/../editor_data.cpp:880)
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: check_and_update_scene (editor/scu/../editor_data.cpp:683)
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: set_edited_scene (editor/scu/../editor_data.cpp:745)
```

Possibly related to recent changes to restore past sessions, but there's nothing to restore in this case?

### Steps to reproduce

- Create a new project, edit it
- Quit to project manager
- Re-open the newly created project -> errors

### Minimal reproduction project

Empty project.
FileSystemDock::get_singleton()->set_file_sort(dock_filesystem_file_sort);
	}
	if (p_layout->has_section_key(p_section, "dock_filesystem_file_list_display_mode")) {
		FileSystemDock::FileListDisplayMode dock_filesystem_file_list_display_mode = FileSystemDock::FileListDisplayMode(int(p_layout->get_value(p_section, "dock_filesystem_file_list_display_mode")));
		FileSystemDock::get_singleton()->set_file_list_display_mode(dock_filesystem_file_list_display_mode);
	}
	if (p_layout->has_section_key(p_section, "dock_filesystem_selected_paths")) {
		PackedStringArray dock_filesystem_selected_paths = p_layout->get_value(p_section, "dock_filesystem_selected_paths");
		for (int i = 0; i < dock_filesystem_selected_paths.size(); i++) {
			FileSystemDock::get_singleton()->select_file(dock_filesystem_selected_paths[i]);
		}
	}
	
	PackedStringArray uncollapsed_tis;
	if (p_layout->has_section_key(p_section, "dock_filesystem_uncollapsed_paths")) {
		uncollapsed_tis = p_layout->get_value(p_section, "dock_filesystem_uncollapsed_paths");
	} else {
		uncollapsed_tis = { "res:" };
	}
	if (!uncollapsed_tis.is_empty()) {
		for (int i = 0; i < uncollapsed_tis.size(); i++) {
			TreeItem *uncollapsed_ti = FileSystemDock::get_singleton()->get_tree_control()->get_item_with_metadata(uncollapsed_tis[i], 0);
			if (uncollapsed_ti) {
				uncollapsed_ti->set_collapsed(false);
			}
		}
		FileSystemDock::get_singleton()->get_tree_control()->queue_redraw();
	}
}
void EditorNode::_save_central_editor_layout_to_config(Ref<ConfigFile> p_config_file) {