I18N: Add option to hide en_US locale in `wp_dropdown_languages()`.

Props danieltj for initial patch.
Fixes #44494.

Built from https://develop.svn.wordpress.org/trunk@44514


git-svn-id: http://core.svn.wordpress.org/trunk@44345 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/l10n.php

@@ -1364,6 +1364,7 @@ function wp_get_pomo_file_data( $po_file ) {
  * @since 4.0.0
  * @since 4.3.0 Introduced the `echo` argument.
  * @since 4.7.0 Introduced the `show_option_site_default` argument.
+ * @since 5.1.0 Introduced the `show_option_en_us` argument.
  *
  * @see get_available_languages()
  * @see wp_get_available_translations()
@@ -1382,6 +1383,7 @@ function wp_get_pomo_file_data( $po_file ) {
  *                                                  boolean equivalents. Default 1.
  *     @type bool     $show_available_translations  Whether to show available translations. Default true.
  *     @type bool     $show_option_site_default     Whether to show an option to fall back to the site's locale. Default false.
+ *     @type bool     $show_option_en_us            Whether to show an option for English (United States). Default true.
  * }
  * @return string HTML content
  */
@@ -1398,6 +1400,7 @@ function wp_dropdown_languages( $args = array() ) {
 			'echo'                        => 1,
 			'show_available_translations' => true,
 			'show_option_site_default'    => false,
+			'show_option_en_us'           => true,
 		)
 	);
 
@@ -1461,11 +1464,12 @@ function wp_dropdown_languages( $args = array() ) {
 		);
 	}
 
-	// Always show English.
+	if ( $parsed_args['show_option_en_us'] ) {
 		$structure[] = sprintf(
 			'<option value="" lang="en" data-installed="1"%s>English (United States)</option>',
 			selected( '', $parsed_args['selected'], false )
 		);
+	}
 
 	// List installed languages.
 	foreach ( $languages as $language ) {

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.1-alpha-44513';
+$wp_version = '5.1-alpha-44514';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.