src/vs/workbench/api/browser/mainThreadTreeViews.ts/MainThreadTreeViews/$refresh
class MainThreadTreeViews:	$refresh(treeViewId: string, itemsToRefreshByHandle: { [treeItemHandle: string]: ITreeItem }): Promise<void> {
		this.logService.trace('MainThreadTreeViews#$refresh', treeViewId, itemsToRefreshByHandle);

		const viewer = this.getTreeView(treeViewId);
		const dataProvider = this._dataProviders.get(treeViewId);
		if (viewer && dataProvider) {
			const itemsToRefresh = dataProvider.getItemsToRefresh(itemsToRefreshByHandle);
			return viewer.refresh(itemsToRefresh.length ? itemsToRefresh : undefined);
		}
		return Promise.resolve();
	}