message: [crispy] LRUCache: very minor cleanup.
diff: @@ -132,7 +132,7 @@ public:
  Value& emplace(Key _key, Value _value)
  {
  - assert(!try_get(_key));
  + assert(!contains(_key));
  if (items_.size() == capacity_)
  return evict_one_and_push_front(_key)->second = std::move(_value);
  