src/vs/base/browser/ui/actionbar/actionbar.ts/ActionBar/updateFocusedItem
class ActionBar:	private updateFocusedItem(): void {
		for (let i = 0; i < this.actionsList.children.length; i++) {
			const elem = this.actionsList.children[i];
			if (DOM.isAncestor(DOM.getActiveElement(), elem)) {
				this.focusedItem = i;
				break;
			}
		}
	}