Equivalize isLowerCase and isUpperCase behavior in all platforms #KT-46184

libraries/stdlib/js/src/generated/_LetterChars.kt

@@ -51,17 +51,17 @@ internal fun Char.isLetterImpl(): Boolean {
 }
 
 /**
- * Returns `true` if this character is a lower case letter.
+ * Returns `true` if this character is a lower case letter, or it has contributory property Other_Lowercase.
  */
 internal fun Char.isLowerCaseImpl(): Boolean {
-    return getLetterType() == 1
+    return getLetterType() == 1 || code.isOtherLowercase()
 }
 
 /**
- * Returns `true` if this character is an upper case letter.
+ * Returns `true` if this character is an upper case letter, or it has contributory property Other_Uppercase.
  */
 internal fun Char.isUpperCaseImpl(): Boolean {
-    return getLetterType() == 2
+    return getLetterType() == 2 || code.isOtherUppercase()
 }
 
 /**