Themes: Improve document title output.

Introduces more flexibility in filtering all parts of the document title,the
separator, and a way to short-circuit title generation. Plugins can now also
check for theme support and reliably filter the entire output. See #18548.
Deprecates `wp_title()`.

Fixes #31078.



git-svn-id: https://develop.svn.wordpress.org/trunk@35294 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/feed-rss.php

@@ -11,7 +11,7 @@ $more = 1;
 echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>'; ?>
 <rss version="0.92">
 <channel>
-	<title><?php bloginfo_rss('name'); wp_title_rss(); ?></title>
+	<title><?php wp_title_rss(); ?></title>
 	<link><?php bloginfo_rss('url') ?></link>
 	<description><?php bloginfo_rss('description') ?></description>
 	<lastBuildDate><?php echo mysql2date('D, d M Y H:i:s +0000', get_lastpostmodified('GMT'), false); ?></lastBuildDate>