gfe-relnote: (n/a) Add QuicCircularDeque to third_party/quic/core. Code not used yet. The implementation is based on Chromium's circular_deque(http://shortn/_RLFU0Zrxza), the backing type of Chromium's QuicDeque. The new class can be used by all existing uses of QuicDeque except the one in PacketNumberQueue. PiperOrigin-RevId: 278627694 Change-Id: If52cd23cd38c173b14ccefad57b86c4bcf405392