pgsql: Prevent non-streaming replication connections from being selecte

Prevent non-streaming replication connections from being selected sync slave

This prevents a pg_basebackup backup session that just does a base
backup (no xlog involved at all) from becoming the synchronous slave
and thus blocking all access while it runs.

Also fixes the problem when a higher priority slave shows up it would
become the sync standby before it has reached the STREAMING state, by
making sure we can only switch to a walsender that's actually STREAMING.

Fujii Masao

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/3595a71e9ce90a2d4c812a9bb34dc24ffc492c2b

Modified Files
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src/backend/replication/syncrep.c |    1 +
1 files changed, 1 insertions(+), 0 deletions(-)