pgsql: Tweak find_composite_type_dependencies API a bit more.

Tweak find_composite_type_dependencies API a bit more.

Per discussion with Noah Misch, the previous coding, introduced by
my commit 65377e0b9c0e0397b1598b38b6a7fb8b6f740d39 on 2011-02-06,
was really an abuse of RELKIND_COMPOSITE_TYPE, since the caller in
typecmds.c is actually passing the name of a domain. So go back
having a type name argument, but make the first argument a Relation
rather than just a string so we can tell whether it's a table or
a foreign table and emit the proper error message.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/2c20ba1fd284423e4652f2f6855d257339245e97

Modified Files
--------------
src/backend/commands/tablecmds.c | 25 +++++++++++++------------
src/backend/commands/typecmds.c | 2 +-
src/include/commands/tablecmds.h | 3 ++-
3 files changed, 16 insertions(+), 14 deletions(-)