pgsql: Avoid treating WAL senders as normal backends.

Avoid treating WAL senders as normal backends.

The previous coding treated anything that wasn't an autovacuum launcher
as a normal backend, which is wrong now that we also have WAL senders.

Fujii Masao, reviewed by Robert Haas, Alvaro Herrera, Tom Lane,
and Bernd Helmle.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=a0c75f55394fe904e09f7caee9a8195e3a09c801

Modified Files
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src/backend/postmaster/postmaster.c |   52 +++++++++++++++++++++++++---------
1 files changed, 38 insertions(+), 14 deletions(-)