MDEV-27760 event may non stop replicate in circular semisync setup
MDEV-21117 had to relax own events acceptance condition for a case when a former semisync master server recovers after crash as the semisync slave. That however admitted a possibility for endless event "orbiting" in the non-strict slave gtid mode of semisync circular setup. The same server-id event termination is restored now for the non-strict gtid mode to follow regular rules (that is it's ignored unless @@global.replicate_same_server_id allows it in). To address MDEV-21117 recovery agenda, in the strict gtid mode and the transaction's gtid ordered strictly greater than the current slave gtid state, the same server-id transaction is accepted. The gtid strict mode is safe to accept transactions even if the slave state were not set correct by the user, e.g at the former master. An added test shows a typical out-of-order error at execution so no data corruption is guaranteed in such a case.
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