Query: Preinitialize the `WP` class properties to their default values.

This avoids an `array_keys() expects parameter 1 to be array, null given` PHP warning for the `query_vars` property in `WP::build_query_string()` when disabling request parsing via the `do_parse_request` filter.

Props dd32, SergeyBiryukov.
Fixes #55222.
Built from https://develop.svn.wordpress.org/trunk@52804


git-svn-id: http://core.svn.wordpress.org/trunk@52393 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp.php

@@ -40,7 +40,7 @@ class WP {
 	 * @since 2.0.0
 	 * @var array
 	 */
-	public $query_vars;
+	public $query_vars = array();
 
 	/**
 	 * String parsed to set the query variables.
@@ -48,7 +48,7 @@ class WP {
 	 * @since 2.0.0
 	 * @var string
 	 */
-	public $query_string;
+	public $query_string = '';
 
 	/**
 	 * The request path, e.g. 2015/05/06.
@@ -56,7 +56,7 @@ class WP {
 	 * @since 2.0.0
 	 * @var string
 	 */
-	public $request;
+	public $request = '';
 
 	/**
 	 * Rewrite rule the request matched.
@@ -64,7 +64,7 @@ class WP {
 	 * @since 2.0.0
 	 * @var string
 	 */
-	public $matched_rule;
+	public $matched_rule = '';
 
 	/**
 	 * Rewrite query the request matched.
@@ -72,7 +72,7 @@ class WP {
 	 * @since 2.0.0
 	 * @var string
 	 */
-	public $matched_query;
+	public $matched_query = '';
 
 	/**
 	 * Whether already did the permalink.

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.0-alpha-52802';
+$wp_version = '6.0-alpha-52804';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.