src/vs/workbench/contrib/outline/browser/outlinePane.ts/OutlineTreeSorter/compare
class OutlineTreeSorter:	compare(a: E, b: E): number {
		if (this.order === OutlineSortOrder.ByKind) {
			return this._comparator.compareByType(a, b);
		} else if (this.order === OutlineSortOrder.ByName) {
			return this._comparator.compareByName(a, b);
		} else {
			return this._comparator.compareByPosition(a, b);
		}
	}