Update: Inlining PoolCollection::Fill implementation into Pool In order for us to unify TakeX/FreeX custom methods into a single overload set, we need to unify their constraints. This removes one new T() call from 2 calls in PoolCollectionm which is first step towards removing new() constraint on PoolCollection(and instead preserving it on Pool APIs). Also left a note about thread safety - luckily right now everything is used in a safe manner