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Closes#909 from yaooqinn/906.
Closes#906
e202b70d [Kent Yao] nit
1271e841 [Kent Yao] fix test
d696021f [Kent Yao] [KYUUBI #906] Add SessionEvent to track session status changes
bdd2b875 [Kent Yao] [KYUUBI #906] Add SessionEvent to track session status changes
Authored-by: Kent Yao <yao@apache.org>
Signed-off-by: Kent Yao <yao@apache.org>
f96256ced6