In QUIC, add TimeWaitConnectionInfo to record necessary information of connections which are going to be added to time wait list. Refactor only, no functional change expected, not protected. In the next change, I am going to add more info to this struct (e.g., srtt) PiperOrigin-RevId: 325285116 Change-Id: Iee053bda3f66a77bd0a5bf39d8b1fbb6f6d930b2