Fix toast rewrites in logical decoding.

Commit 325f2ec555 introduced pg_class.relwrite to skip operations on
tables created as part of a heap rewrite during DDL. It links such
transient heaps to the original relation OID via this new field in
pg_class but forgot to do anything about toast tables. So, logical
decoding was not able to skip operations on internally created toast
tables. This leads to an error when we tried to decode the WAL for the
next operation for which it appeared that there is a toast data where
actually it didn't have any toast data.

To fix this, we set pg_class.relwrite for internally created toast tables
as well which allowed skipping operations on them during logical decoding.

Author: Bertrand Drouvot
Reviewed-by: David Zhang, Amit Kapila
Backpatch-through: 11, where it was introduced
Discussion: https://postgr.es/m/b5146fb1-ad9e-7d6e-f980-98ed68744a7c@amazon.com

src/include/catalog/toasting.h

@@ -24,7 +24,7 @@
  */
 extern void NewRelationCreateToastTable(Oid relOid, Datum reloptions);
 extern void NewHeapCreateToastTable(Oid relOid, Datum reloptions,
-									LOCKMODE lockmode);
+									LOCKMODE lockmode, Oid OIDOldToast);
 extern void AlterTableCreateToastTable(Oid relOid, Datum reloptions,
 									   LOCKMODE lockmode);
 extern void BootstrapToastTable(char *relName,

src/include/commands/tablecmds.h

@@ -70,6 +70,8 @@ extern void RenameRelationInternal(Oid myrelid,
 								   const char *newrelname, bool is_internal,
 								   bool is_index);
 
+extern void ResetRelRewrite(Oid myrelid);
+
 extern void find_composite_type_dependencies(Oid typeOid,
 											 Relation origRelation,
 											 const char *origTypeName);