Implement listeners, connection, endpoints for `FuzzingEventEngine`.
Allows the fuzzer to select write sizes and delays, connection delays,
and port assignments.
I made a few modifications to the test suite to admit this event engine
to pass the client & server tests:
1. the test factories return shared_ptr<> to admit us to return the same
event engine for both the oracle and the implementation - necessary
because FuzzingEventEngine forms a closed world of addresses & ports.
2. removed the WaitForSingleOwner calls - these seem unnecessary, and we
don't ask our users to do this - tested existing linux tests 1000x
across debug, asan, tsan with this change
Additionally, the event engine overrides the global port picker logic so
that port assignments are made by the fuzzer too.
This PR is a step along a longer journey, and has some outstanding
brethren PR's, and some follow-up work:
* #32603 will convert all the core e2e tests into a more malleable form
* we'll then use #32667 to turn all of these into fuzzers
* finally we'll integrate this into that work and turn all core e2e
tests into fuzzers over timer & callback reorderings and io
size/spacings
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Co-authored-by: ctiller <ctiller@users.noreply.github.com>
Also actually add the port parameter to grpc_recycle_unused_port.
Also remove the downsizing gpr_realloc in the recycle codepath, which is
unnecessary and can free the pointer.