Test the bdr.pg_stat_replication view

Makefile.in

@@ -326,6 +326,7 @@ REGRESSCHECKS= \
 	catalog \
 	terminate \
 	skipchanges \
+	pgstatreplicationslots \
 	$(DDLREGRESSCHECKS) \
 	dml/basic dml/contrib dml/delete_pk dml/extended dml/missing_pk dml/toasted \
 	$(EXTRAREGRESSCHECKS) \

expected/pgreplicationslots.out

@@ -0,0 +1,14 @@
+--
+-- Access the extended bdr.pg_replication_slots view
+-- with the data backported from 9.5 and 9.6.
+--
+SELECT 1
+FROM pg_stat_replication
+INNER JOIN bdr.pg_replication_slots USING (pid)
+WHERE confirmed_flush_lsn IS NOT NULL;
+ ?column? 
+----------
+        1
+        1
+(2 rows)
+

sql/pgreplicationslots.sql

@@ -0,0 +1,9 @@
+--
+-- Access the extended bdr.pg_replication_slots view
+-- with the data backported from 9.5 and 9.6.
+--
+
+SELECT 1
+FROM pg_stat_replication
+INNER JOIN bdr.pg_replication_slots USING (pid)
+WHERE confirmed_flush_lsn IS NOT NULL;