General: Correctly detect large floats in is_serialized().

Props killerbishop, donmhico, hoythan.
Fixes #46570.
Built from https://develop.svn.wordpress.org/trunk@45754


git-svn-id: http://core.svn.wordpress.org/trunk@45565 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/functions.php

@@ -528,7 +528,7 @@ function is_serialized( $data, $strict = true ) {
 		case 'i':
 		case 'd':
 			$end = $strict ? '$' : '';
-			return (bool) preg_match( "/^{$token}:[0-9.E-]+;$end/", $data );
+			return (bool) preg_match( "/^{$token}:[0-9.E+-]+;$end/", $data );
 	}
 	return false;
 }