Add pg_dump tests for CREATE STATISTICS

CREATE STATISTICS pg_dump support code was not covered at all by
previous tests.

Discussion: https://postgr.es/m/20170503172746.rwftidszir67sgk7@alvherre.pgsql

src/bin/pg_dump/t/002_pg_dump.pl

@@ -4920,6 +4920,74 @@ qr/CREATE TRANSFORM FOR integer LANGUAGE sql \(FROM SQL WITH FUNCTION pg_catalog
 			role                     => 1,
 			section_post_data        => 1, }, },
 
+	'CREATE STATISTICS extended_stats_no_options' => {
+		all_runs     => 1,
+		catch_all    => 'CREATE ... commands',
+		create_order => 97,
+		create_sql   => 'CREATE STATISTICS dump_test.test_ext_stats_no_options
+							ON (col1, col2) FROM dump_test.test_fifth_table',
+		regexp => qr/^
+			\QCREATE STATISTICS dump_test.test_ext_stats_no_options ON (col1, col2) FROM test_fifth_table;\E
+		    /xms,
+		like => {
+			binary_upgrade          => 1,
+			clean                   => 1,
+			clean_if_exists         => 1,
+			createdb                => 1,
+			defaults                => 1,
+			exclude_test_table      => 1,
+			exclude_test_table_data => 1,
+			no_blobs                => 1,
+			no_privs                => 1,
+			no_owner                => 1,
+			only_dump_test_schema   => 1,
+			pg_dumpall_dbprivs      => 1,
+			schema_only             => 1,
+			section_post_data       => 1,
+			test_schema_plus_blobs  => 1,
+			with_oids               => 1, },
+		unlike => {
+			exclude_dump_test_schema => 1,
+			only_dump_test_table     => 1,
+			pg_dumpall_globals       => 1,
+			pg_dumpall_globals_clean => 1,
+			role                     => 1,
+			section_pre_data         => 1, }, },
+
+	'CREATE STATISTICS extended_stats_options' => {
+		all_runs     => 1,
+		catch_all    => 'CREATE ... commands',
+		create_order => 97,
+		create_sql   => 'CREATE STATISTICS dump_test.test_ext_stats_using
+							WITH (ndistinct) ON (col1, col2) FROM dump_test.test_fifth_table',
+		regexp => qr/^
+			\QCREATE STATISTICS dump_test.test_ext_stats_using WITH (ndistinct) ON (col1, col2) FROM test_fifth_table;\E
+		    /xms,
+		like => {
+			binary_upgrade          => 1,
+			clean                   => 1,
+			clean_if_exists         => 1,
+			createdb                => 1,
+			defaults                => 1,
+			exclude_test_table      => 1,
+			exclude_test_table_data => 1,
+			no_blobs                => 1,
+			no_privs                => 1,
+			no_owner                => 1,
+			only_dump_test_schema   => 1,
+			pg_dumpall_dbprivs      => 1,
+			schema_only             => 1,
+			section_post_data       => 1,
+			test_schema_plus_blobs  => 1,
+			with_oids               => 1, },
+		unlike => {
+			exclude_dump_test_schema => 1,
+			only_dump_test_table     => 1,
+			pg_dumpall_globals       => 1,
+			pg_dumpall_globals_clean => 1,
+			role                     => 1,
+			section_pre_data         => 1, }, },
+
 	'CREATE SEQUENCE test_table_col1_seq' => {
 		all_runs  => 1,
 		catch_all => 'CREATE ... commands',