I18N: Check that `$wp_locale` global is set before calling its methods.

This avoids a fatal error if these functions are called in a mu-plugin before `$wp_locale` is set:
* `wp_get_list_item_separator()`
* `wp_get_word_count_type()`

Follow-up to [52929], [52933], [55279], [55295].

Props kraftbj.
Fixes #56698.
Built from https://develop.svn.wordpress.org/trunk@55351


git-svn-id: http://core.svn.wordpress.org/trunk@54884 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-locale.php

@@ -235,7 +235,7 @@ class WP_Locale {
 
 		$this->number_format['decimal_point'] = ( 'number_format_decimal_point' === $decimal_point ) ? '.' : $decimal_point;
 
-		/* translators: used between list items, there is a space after the comma */
+		/* translators: Used between list items, there is a space after the comma. */
 		$this->list_item_separator = __( ', ' );
 
 		// Set text direction.

wp-includes/l10n.php

@@ -1807,6 +1807,12 @@ function translate_settings_using_i18n_schema( $i18n_schema, $settings, $textdom
 function wp_get_list_item_separator() {
 	global $wp_locale;
 
+	if ( ! ( $wp_locale instanceof WP_Locale ) ) {
+		// Default value of WP_Locale::get_list_item_separator().
+		/* translators: Used between list items, there is a space after the comma. */
+		return __( ', ' );
+	}
+
 	return $wp_locale->get_list_item_separator();
 }
 
@@ -1823,5 +1829,10 @@ function wp_get_list_item_separator() {
 function wp_get_word_count_type() {
 	global $wp_locale;
 
+	if ( ! ( $wp_locale instanceof WP_Locale ) ) {
+		// Default value of WP_Locale::get_word_count_type().
+		return 'words';
+	}
+
 	return $wp_locale->get_word_count_type();
 }

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.2-beta2-55350';
+$wp_version = '6.2-beta2-55351';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.