src/vs/workbench/contrib/codeEditor/browser/outline/documentSymbolsOutline.ts/DocumentSymbolsOutline/activeElement
class DocumentSymbolsOutline:	get activeElement(): DocumentSymbolItem | undefined {
		const posistion = this._editor.getPosition();
		if (!posistion || !this._outlineModel) {
			return undefined;
		} else {
			return this._outlineModel.getItemEnclosingPosition(posistion);
		}
	}