src/vs/workbench/services/dialogs/electron-sandbox/fileDialogService.ts/FileDialogService/toNativeSaveDialogOptions
class FileDialogService:	private toNativeSaveDialogOptions(options: ISaveDialogOptions): SaveDialogOptions {
		options.defaultUri = options.defaultUri ? URI.file(options.defaultUri.path) : undefined;
		return {
			defaultPath: options.defaultUri && options.defaultUri.fsPath,
			buttonLabel: options.saveLabel,
			filters: options.filters,
			title: options.title
		};
	}