Merge 10.4 into 10.5

mysql-test/include/ctype_casefolding.inc

@@ -0,0 +1,18 @@
+CREATE OR REPLACE TABLE case_folding AS SELECT 0 AS code, SPACE(32) AS c LIMIT 0;
+SHOW CREATE TABLE case_folding;
+# Uncode code points that have a variable length case mapping in utf8
+# (e.g.  LOWER('2-byte-character') -> '3-byte-character'
+INSERT INTO case_folding (code) VALUES
+(0x23A),
+(0x23E),
+(0x23F),
+(0x240),
+(0x250),
+(0x251),
+(0x252),
+(0x26B),
+(0x271),
+(0x27D);
+UPDATE case_folding SET c=CHAR(code USING ucs2);
+SELECT HEX(code), HEX(LOWER(c)), HEX(UPPER(c)), c FROM case_folding;
+DROP TABLE case_folding;