src/vs/base/browser/ui/actionbar/actionViewItems.ts/BaseActionViewItem/constructor
class BaseActionViewItem:	constructor(context: unknown, action: IAction, protected options: IBaseActionViewItemOptions = {}) {
		super();

		this._context = context || this;
		this._action = action;

		if (action instanceof Action) {
			this._register(action.onDidChange(event => {
				if (!this.element) {
					// we have not been rendered yet, so there
					// is no point in updating the UI
					return;
				}

				this.handleActionChangeEvent(event);
			}));
		}
	}