Previously this code used the tcpip error space. Since it is no longer part of
netstack, it can use the sentry's error space (except for a few cases where
there is still some shared code. This reduces the number of error space
conversions required for hot Unix socket operations.
PiperOrigin-RevId: 218541611
Change-Id: I3d13047006a8245b5dfda73364d37b8a453784bb