pgsql: Fix a tiny race condition in predicate locking. Need to hold the

Fix a tiny race condition in predicate locking. Need to hold the lock while
examining the head of predicate locks list. Also, fix the comment of
RemoveTargetIfNoLongerUsed, it was neglected when we changed the way update
chains are handled.

Kevin Grittner

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/60b142b9a6f413a92665766a1f265b361f68c20b

Modified Files
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src/backend/storage/lmgr/predicate.c |    7 +++----
1 files changed, 3 insertions(+), 4 deletions(-)