Clean-ups for MDEV-10132 utf8_thai_520_w2 collation:

- Changing strnxfrm_multiply from 8 to 4, as agreed with Pruet Boonma
- Adjusting tests

mysql-test/r/ctype_uca_th.result

+SELECT ID, SORTLEN, COLLATION_NAME, CHARACTER_SET_NAME
+FROM INFORMATION_SCHEMA.COLLATIONS
+WHERE COLLATION_NAME LIKE 'utf8_thai_520_w2';
+ID	SORTLEN	COLLATION_NAME	CHARACTER_SET_NAME
+578	4	utf8_thai_520_w2	utf8
 SET NAMES utf8;
 #
 # Testing strnxfrm

mysql-test/suite/engines/funcs/r/db_alter_collate_ascii.result

@@ -84,6 +84,7 @@ utf8_vietnamese_ci	utf8	215		#	#
 utf8_general_mysql500_ci	utf8	223		#	#
 utf8_croatian_ci	utf8	576		#	#
 utf8_myanmar_ci	utf8	577		#	#
+utf8_thai_520_w2	utf8	578		#	#
 ucs2_general_ci	ucs2	35	Yes	#	#
 ucs2_bin	ucs2	90		#	#
 ucs2_unicode_ci	ucs2	128		#	#

mysql-test/suite/engines/funcs/r/db_alter_collate_utf8.result

@@ -84,6 +84,7 @@ utf8_vietnamese_ci	utf8	215		#	#
 utf8_general_mysql500_ci	utf8	223		#	#
 utf8_croatian_ci	utf8	576		#	#
 utf8_myanmar_ci	utf8	577		#	#
+utf8_thai_520_w2	utf8	578		#	#
 ucs2_general_ci	ucs2	35	Yes	#	#
 ucs2_bin	ucs2	90		#	#
 ucs2_unicode_ci	ucs2	128		#	#

mysql-test/suite/sys_vars/inc/collation_basic.inc

@@ -152,6 +152,8 @@ eval SET $collation_variable = utf8_esperanto_ci;
 eval SELECT $collation_variable;
 eval SET $collation_variable = utf8_hungarian_ci;
 eval SELECT $collation_variable;
+eval SET $collation_variable = utf8_thai_520_w2;
+eval SELECT $collation_variable;
 eval SET $collation_variable = ucs2_general_ci;
 eval SELECT $collation_variable;
 eval SET $collation_variable = ucs2_bin;

mysql-test/suite/sys_vars/r/collation_connection_basic.result

@@ -374,6 +374,10 @@ SET @@session.collation_connection = utf8_hungarian_ci;
 SELECT @@session.collation_connection;
 @@session.collation_connection
 utf8_hungarian_ci
+SET @@session.collation_connection = utf8_thai_520_w2;
+SELECT @@session.collation_connection;
+@@session.collation_connection
+utf8_thai_520_w2
 SET @@session.collation_connection = ucs2_general_ci;
 SELECT @@session.collation_connection;
 @@session.collation_connection
@@ -883,6 +887,10 @@ SET @@global.collation_connection = utf8_hungarian_ci;
 SELECT @@global.collation_connection;
 @@global.collation_connection
 utf8_hungarian_ci
+SET @@global.collation_connection = utf8_thai_520_w2;
+SELECT @@global.collation_connection;
+@@global.collation_connection
+utf8_thai_520_w2
 SET @@global.collation_connection = ucs2_general_ci;
 SELECT @@global.collation_connection;
 @@global.collation_connection

mysql-test/suite/sys_vars/r/collation_database_basic.result

@@ -376,6 +376,10 @@ SET @@session.collation_database = utf8_hungarian_ci;
 SELECT @@session.collation_database;
 @@session.collation_database
 utf8_hungarian_ci
+SET @@session.collation_database = utf8_thai_520_w2;
+SELECT @@session.collation_database;
+@@session.collation_database
+utf8_thai_520_w2
 SET @@session.collation_database = ucs2_general_ci;
 SELECT @@session.collation_database;
 @@session.collation_database
@@ -885,6 +889,10 @@ SET @@global.collation_database = utf8_hungarian_ci;
 SELECT @@global.collation_database;
 @@global.collation_database
 utf8_hungarian_ci
+SET @@global.collation_database = utf8_thai_520_w2;
+SELECT @@global.collation_database;
+@@global.collation_database
+utf8_thai_520_w2
 SET @@global.collation_database = ucs2_general_ci;
 SELECT @@global.collation_database;
 @@global.collation_database

mysql-test/suite/sys_vars/r/collation_server_basic.result

@@ -373,6 +373,10 @@ SET @@session.collation_server = utf8_hungarian_ci;
 SELECT @@session.collation_server;
 @@session.collation_server
 utf8_hungarian_ci
+SET @@session.collation_server = utf8_thai_520_w2;
+SELECT @@session.collation_server;
+@@session.collation_server
+utf8_thai_520_w2
 SET @@session.collation_server = ucs2_general_ci;
 SELECT @@session.collation_server;
 @@session.collation_server
@@ -882,6 +886,10 @@ SET @@global.collation_server = utf8_hungarian_ci;
 SELECT @@global.collation_server;
 @@global.collation_server
 utf8_hungarian_ci
+SET @@global.collation_server = utf8_thai_520_w2;
+SELECT @@global.collation_server;
+@@global.collation_server
+utf8_thai_520_w2
 SET @@global.collation_server = ucs2_general_ci;
 SELECT @@global.collation_server;
 @@global.collation_server

mysql-test/t/ctype_uca_th.test

 
+SELECT ID, SORTLEN, COLLATION_NAME, CHARACTER_SET_NAME
+FROM INFORMATION_SCHEMA.COLLATIONS
+WHERE COLLATION_NAME LIKE 'utf8_thai_520_w2';
 
 SET NAMES utf8;
 

strings/ctype-uca.c

@@ -35954,7 +35954,7 @@ struct charset_info_st my_charset_utf8_thai_520_w2=
     &my_unicase_unicode520,/* caseinfo   */
     NULL,                /* state_map    */
     NULL,                /* ident_map    */
-    8,                   /* strxfrm_multiply */
+    4,                   /* strxfrm_multiply */
     1,                   /* caseup_multiply  */
     1,                   /* casedn_multiply  */
     1,                   /* mbminlen     */