it's xtradb bug. eventually in the test case it tries to put some garbage into a row of the I_S.INNODB_SYS_INDEXES table, that fails, and the error is propagated all the way up. The assertion in the server fires because the error is not sent to the user. I'll fix that - the server will send a generic error if an I_S plugin failed without reporting an error. But the real bug is trying to put garbage into INNODB_SYS_INDEXES. This should've not happened in the first place.
it's xtradb bug. eventually in the test case it tries to put some garbage into a row of the I_S.INNODB_ SYS_INDEXES table, that fails, and the error is propagated all the way up. The assertion in the server fires because the error is not sent to the user. I'll fix that - the server will send a generic error if an I_S plugin failed without reporting an error. But the real bug is trying to put garbage into INNODB_SYS_INDEXES. This should've not happened in the first place.