Use zend_string_to(upper|lower)() API directly

Author: Girgias

ext/standard/array.c

@@ -4529,9 +4529,9 @@ PHP_FUNCTION(array_change_key_case)
 			entry = zend_hash_index_update(Z_ARRVAL_P(return_value), num_key, entry);
 		} else {
 			if (change_to_upper) {
-				new_key = php_string_toupper(string_key);
+				new_key = zend_string_toupper(string_key);
 			} else {
-				new_key = php_string_tolower(string_key);
+				new_key = zend_string_tolower(string_key);
 			}
 			entry = zend_hash_update(Z_ARRVAL_P(return_value), new_key, entry);
 			zend_string_release_ex(new_key, 0);

ext/standard/string.c

@@ -3120,7 +3120,7 @@ static zend_string *php_str_to_str_i_ex(zend_string *haystack, const char *lc_ha
 		char *e;
 
 		if (ZSTR_LEN(needle) == str_len) {
-			lc_needle = php_string_tolower(needle);
+			lc_needle = zend_string_tolower(needle);
 			end = lc_haystack + ZSTR_LEN(haystack);
 			for (p = lc_haystack; (r = (char*)php_memnstr(p, ZSTR_VAL(lc_needle), ZSTR_LEN(lc_needle), end)); p = r + ZSTR_LEN(lc_needle)) {
 				if (!new_str) {
@@ -3141,7 +3141,7 @@ static zend_string *php_str_to_str_i_ex(zend_string *haystack, const char *lc_ha
 			const char *n;
 			const char *endp = o + ZSTR_LEN(haystack);
 
-			lc_needle = php_string_tolower(needle);
+			lc_needle = zend_string_tolower(needle);
 			n = ZSTR_VAL(lc_needle);
 
 			while ((o = (char*)php_memnstr(o, n, ZSTR_LEN(lc_needle), endp))) {
@@ -3185,7 +3185,7 @@ static zend_string *php_str_to_str_i_ex(zend_string *haystack, const char *lc_ha
 nothing_todo:
 		return zend_string_copy(haystack);
 	} else {
-		lc_needle = php_string_tolower(needle);
+		lc_needle = zend_string_tolower(needle);
 
 		if (memcmp(lc_haystack, ZSTR_VAL(lc_needle), ZSTR_LEN(lc_needle))) {
 			zend_string_release_ex(lc_needle, 0);