[ISSUE-435][PART-A]Support receiving traceOn signal.

[BeautyyuYanli]

What is the purpose of the change

Relate to #435

Support receiving traceOn signal, which indicates whether to disable message trace.

Brief changelog

• add interface SendResult::getTraceOn()
• complete extFields according to this

Verifying this change

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[ShannonDing]

LGTM