Split out pg_operator.h function declarations to new file pg_operator_fn.h.

Commit a2e35b53c3 added an #include of catalog/objectaddress.h to
pg_operator.h, making it impossible for client-side code to #include
pg_operator.h.  It's not entirely clear whether any client-side code needs
to include pg_operator.h, but it seems prudent to assume that there is some
such code somewhere.  Therefore, split off the function definitions into a
new file pg_operator_fn.h, similarly to what we've done for some other
catalog header files.

Back-patch of part of commit 0dab5ef39b.

src/backend/catalog/pg_operator.c

@@ -26,6 +26,7 @@
 #include "catalog/objectaccess.h"
 #include "catalog/pg_namespace.h"
 #include "catalog/pg_operator.h"
+#include "catalog/pg_operator_fn.h"
 #include "catalog/pg_proc.h"
 #include "catalog/pg_type.h"
 #include "miscadmin.h"

src/backend/commands/operatorcmds.c

@@ -39,6 +39,7 @@
 #include "catalog/dependency.h"
 #include "catalog/indexing.h"
 #include "catalog/pg_operator.h"
+#include "catalog/pg_operator_fn.h"
 #include "catalog/pg_type.h"
 #include "commands/alter.h"
 #include "commands/defrem.h"

src/include/catalog/pg_operator.h

@@ -23,8 +23,6 @@
 #define PG_OPERATOR_H
 
 #include "catalog/genbki.h"
-#include "catalog/objectaddress.h"
-#include "nodes/pg_list.h"
 
 /* ----------------
  *		pg_operator definition.  cpp turns this into
@@ -1822,19 +1820,4 @@ DESCR("delete array element");
 DATA(insert OID = 3287 (  "#-"	   PGNSP PGUID b f f 3802 1009 3802 0 0 jsonb_delete_path - - ));
 DESCR("delete path");
 
-/*
- * function prototypes
- */
-extern ObjectAddress OperatorCreate(const char *operatorName,
-			   Oid operatorNamespace,
-			   Oid leftTypeId,
-			   Oid rightTypeId,
-			   Oid procedureId,
-			   List *commutatorName,
-			   List *negatorName,
-			   Oid restrictionId,
-			   Oid joinId,
-			   bool canMerge,
-			   bool canHash);
-
 #endif   /* PG_OPERATOR_H */

src/include/catalog/pg_operator_fn.h

@@ -0,0 +1,32 @@
+/*-------------------------------------------------------------------------
+ *
+ * pg_operator_fn.h
+*	 prototypes for functions in catalog/pg_operator.c
+ *
+ *
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/catalog/pg_operator_fn.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef PG_OPERATOR_FN_H
+#define PG_OPERATOR_FN_H
+
+#include "catalog/objectaddress.h"
+#include "nodes/pg_list.h"
+
+extern ObjectAddress OperatorCreate(const char *operatorName,
+			   Oid operatorNamespace,
+			   Oid leftTypeId,
+			   Oid rightTypeId,
+			   Oid procedureId,
+			   List *commutatorName,
+			   List *negatorName,
+			   Oid restrictionId,
+			   Oid joinId,
+			   bool canMerge,
+			   bool canHash);
+
+#endif   /* PG_OPERATOR_FN_H */