Unexpected disconnections from the proxy in `asynctst` stress test about rpc-frmwrk

[zhiming99]

Fixed in the commit a93922b. The reason is the incorrect handling of immediate return of handshake,
which happens rarely, but likey when system load is high. The solution is to replace the incorrect handling with that from async return, which has proved to be correct all the time.

[zhiming99]

New unexpected disconnection found in this stress test. The error report is CIfOpenPortTask failed with 0x80010003, and the proxy state is stateConnected. The network traffic shows the proxy actively close the connection right before calling the first request LongWait. It is very difficult to reproduce this bug. And so far only once.

[zhiming99]

The last one is not fixed yet. The latest test shows CPythonRpcSvc_CliSkel failed to open its port. And still trying to determine whether the failure occurs in the reqfwdr or in the proxy.

[zhiming99]

The last one is not fixed yet. The latest test shows CPythonRpcSvc_CliSkel failed to open its port. And still trying to determine whether the failure occurs in the reqfwdr or in the proxy.

The latest test shows the CUnixSockStmServerRelay failed to start with error -2 or 0x80010003. the reason is still unknown.

[zhiming99]

cannot reproduce any more. probably fixed by this commit ede110c. So it will be closed when the associated PR is submitted.