General: Replace older-style PHP type conversion functions with type casts.

This improves performance, readability, and consistency throughout core.

* `intval()` → `(int)`
* `strval()` → `(string)`
* `floatval()` → `(float)`

Props ayeshrajans.
Fixes #42918.

git-svn-id: https://develop.svn.wordpress.org/trunk@49108 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/http.php

@@ -668,7 +668,7 @@ function ms_allowed_http_request_hosts( $is_external, $host ) {
  */
 function wp_parse_url( $url, $component = -1 ) {
 	$to_unset = array();
-	$url      = strval( $url );
+	$url      = (string) $url;
 
 	if ( '//' === substr( $url, 0, 2 ) ) {
 		$to_unset[] = 'scheme';