When switch from QUIC BBR to BBRv2, use BBR's cwnd as the initial cwnd of BBRv2.
Protected by quic_reloadable_flag_quic_copy_bbr_cwnd_to_bbr2.
PiperOrigin-RevId: 330988495
Change-Id: I101432ec8e685a27f310f39ab4aaab98779de420
QUICHE (QUIC, Http/2, Etc) is Google‘s implementation of QUIC and related protocols. It powers Chromium as well as Google’s QUIC servers and some other projects.
