src/vs/base/common/map.ts/LinkedMap/get
class LinkedMap:	get(key: K, touch: Touch = Touch.None): V | undefined {
		const item = this._map.get(key);
		if (!item) {
			return undefined;
		}
		if (touch !== Touch.None) {
			this.touch(item, touch);
		}
		return item.value;
	}