pgsql: Fix relcache reference leak in refresh_by_match_merge().

Fix relcache reference leak in refresh_by_match_merge().

One path through the loop over indexes forgot to do index_close(). Rather
than adding a fourth call, restructure slightly so that there's only one.

In passing, get rid of an unnecessary syscache lookup: the pg_index struct
for the index is already available from its relcache entry.

Per report from YAMAMOTO Takashi, though this is a bit different from his
suggested patch. This is new code in HEAD, so no need for back-patch.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/f7271c44278352516ec66b2de311952ce330b6d5

Modified Files
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src/backend/commands/matview.c | 41 +++++++++++++---------------------------
1 file changed, 13 insertions(+), 28 deletions(-)