pgsql: Make CheckIndexCompatible simpler and more bullet-proof.

Make CheckIndexCompatible simpler and more bullet-proof.

This gives up the "don't rewrite the index" behavior in a couple of
relatively unimportant cases, such as changing between an array type
and an unconstrained domain over that array type, in return for
making this code more future-proof.

Noah Misch

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/6eb71ac5527a94be443bc66e68b47b04979906e4

Modified Files
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src/backend/commands/indexcmds.c          |  105 ++++++++++++++---------------
src/test/regress/expected/alter_table.out |    9 +++
src/test/regress/sql/alter_table.sql      |    8 ++
3 files changed, 67 insertions(+), 55 deletions(-)