MultiplexChannelState::MultiplexChannelState()
    : requestedReadAmount{0}
    , freeWriteAmount{0}
    , connected{true}
    , close_after_write{false}
{
}

Constructs a class that represents the state of aMultiplexChannel. The state is a copy of the original state, and sets requested read and free write amount to 0, and marks the channel as connected.