pgsql: Fix some minor issues in view pretty-printing.

Fix some minor issues in view pretty-printing.

Code review for commit 2f582f76b1945929ff07116cd4639747ce9bb8a1: don't use
a static variable for what ought to be a deparse_context field, fix
non-multibyte-safe test for spaces, avoid useless and potentially O(N^2)
(though admittedly with a very small constant) calculations of wrap
positions when we aren't going to wrap.

Branch
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REL9_2_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/7ec225d3d615694f308c43d8449861c8e8b1b6aa

Modified Files
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doc/src/sgml/func.sgml | 11 +-
src/backend/utils/adt/ruleutils.c | 215 +++++++++++++++++++-----------------
2 files changed, 119 insertions(+), 107 deletions(-)