Formatting: In `wp_validate_redirect()`, normalize the path when validating the location for relative URLs, to account for Windows paths.

Props peterwilsoncc, rconde, jmmathc, mat-lipe, Sixes, justinahinon, cmagrin, daxelrod, SergeyBiryukov.
Merges [46472] to the 5.2 branch.
Fixes #47980.
Built from https://develop.svn.wordpress.org/branches/5.2@46473


git-svn-id: http://core.svn.wordpress.org/branches/5.2@46271 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/pluggable.php

@@ -1400,6 +1400,7 @@ if ( ! function_exists( 'wp_validate_redirect' ) ) :
 			$path = '';
 			if ( ! empty( $_SERVER['REQUEST_URI'] ) ) {
 				$path = dirname( parse_url( 'http://placeholder' . $_SERVER['REQUEST_URI'], PHP_URL_PATH ) . '?' );
+				$path = wp_normalize_path( $path );
 			}
 			$location = '/' . ltrim( $path . '/', '/' ) . $location;
 		}

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.2.4-alpha-46406';
+$wp_version = '5.2.4-alpha-46473';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.