QUIC: limit in-flight bytes by congestion window. Previously, in-flight byte counter and congestion window were properly maintained, but the limit was not properly implemented. Now a new datagram is sent only if in-flight byte counter is less than window. The limit is datagram-based, which means that a single datagram may lead to exceeding the limit, but the next one will not be sent.

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


have=NGX_SUPPRESS_WARN . auto/have

have=NGX_SMP . auto/have