pgsql: Remove reltarget_has_non_vars flag.

Remove reltarget_has_non_vars flag.

Commit b12fd41c6 added a "reltarget_has_non_vars" field to RelOptInfo,
but failed to maintain it accurately.  Since its only purpose was to skip
calls to has_parallel_hazard() in the simple case where a rel's targetlist
is all Vars, and that call is really pretty cheap in that case anyway, it
seems like this is just a case of premature optimization.  Let's drop the
flag and do the calls unconditionally until it's proven that we need more
smarts here.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/3303ea1a327b41d3b406d7be7a5ce2901e561066

Modified Files
--------------
src/backend/nodes/outfuncs.c             | 1 -
src/backend/optimizer/path/allpaths.c    | 9 +++------
src/backend/optimizer/util/placeholder.c | 2 --
src/backend/optimizer/util/relnode.c     | 5 +----
src/include/nodes/relation.h             | 2 --
5 files changed, 4 insertions(+), 15 deletions(-)