Fix citext upgrade script to update derived copies of pg_type.typcollation.

If the existing citext type has not merely been created, but used in any
tables, then the upgrade script wasn't doing enough.  We have to update
attcollation for each citext table column, and indcollation for each citext
index column, as well.  Per report from Rudolf van der Leeden.

contrib/citext/citext--unpackaged--1.0.sql

@@ -81,11 +81,49 @@ ALTER EXTENSION citext ADD function translate(citext,citext,text);
 --
 -- As of 9.1, type citext should be marked collatable.  There is no ALTER TYPE
 -- command for this, so we have to do it by poking the pg_type entry directly.
+-- We have to poke any derived copies in pg_attribute or pg_index as well.
 -- Notes: 100 is the OID of the "pg_catalog.default" collation --- it seems
 -- easier and more reliable to hard-wire that here than to pull it out of
--- pg_collation.  Also, we don't need a pg_depend entry since the default
+-- pg_collation.  Also, we don't need to make pg_depend entries since the
--- collation is pinned.
+-- default collation is pinned.
 --
 
 UPDATE pg_catalog.pg_type SET typcollation = 100
 WHERE oid = 'citext'::pg_catalog.regtype;
+
+UPDATE pg_catalog.pg_attribute SET attcollation = 100
+WHERE atttypid = 'citext'::pg_catalog.regtype;
+
+UPDATE pg_catalog.pg_index SET indcollation[0] = 100
+WHERE indclass[0] IN (SELECT oid FROM pg_catalog.pg_opclass
+                      WHERE opcintype = 'citext'::pg_catalog.regtype);
+
+UPDATE pg_catalog.pg_index SET indcollation[1] = 100
+WHERE indclass[1] IN (SELECT oid FROM pg_catalog.pg_opclass
+                      WHERE opcintype = 'citext'::pg_catalog.regtype);
+
+UPDATE pg_catalog.pg_index SET indcollation[2] = 100
+WHERE indclass[2] IN (SELECT oid FROM pg_catalog.pg_opclass
+                      WHERE opcintype = 'citext'::pg_catalog.regtype);
+
+UPDATE pg_catalog.pg_index SET indcollation[3] = 100
+WHERE indclass[3] IN (SELECT oid FROM pg_catalog.pg_opclass
+                      WHERE opcintype = 'citext'::pg_catalog.regtype);
+
+UPDATE pg_catalog.pg_index SET indcollation[4] = 100
+WHERE indclass[4] IN (SELECT oid FROM pg_catalog.pg_opclass
+                      WHERE opcintype = 'citext'::pg_catalog.regtype);
+
+UPDATE pg_catalog.pg_index SET indcollation[5] = 100
+WHERE indclass[5] IN (SELECT oid FROM pg_catalog.pg_opclass
+                      WHERE opcintype = 'citext'::pg_catalog.regtype);
+
+UPDATE pg_catalog.pg_index SET indcollation[6] = 100
+WHERE indclass[6] IN (SELECT oid FROM pg_catalog.pg_opclass
+                      WHERE opcintype = 'citext'::pg_catalog.regtype);
+
+UPDATE pg_catalog.pg_index SET indcollation[7] = 100
+WHERE indclass[7] IN (SELECT oid FROM pg_catalog.pg_opclass
+                      WHERE opcintype = 'citext'::pg_catalog.regtype);
+
+-- somewhat arbitrarily, we assume no citext indexes have more than 8 columns