Avoid double path separators in `load_theme_textdomain()`. Fixes #29122. Props bradyvercher

Built from https://develop.svn.wordpress.org/trunk@29984


git-svn-id: http://core.svn.wordpress.org/trunk@29726 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/l10n.php

@@ -661,7 +661,7 @@ function load_theme_textdomain( $domain, $path = false ) {
 		$path = get_template_directory();
 
 	// Load the textdomain according to the theme
-	$mofile = "{$path}/{$locale}.mo";
+	$mofile = untrailingslashit( $path ) . "/{$locale}.mo";
 	if ( $loaded = load_textdomain( $domain, $mofile ) )
 		return $loaded;