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/class-http.php

@@ -752,7 +752,7 @@ class WP_Http {
 		}
 
 		// Cast the Response Code to an int.
-		$response['code'] = intval( $response['code'] );
+		$response['code'] = (int) $response['code'];
 
 		return array(
 			'response' => $response,