Widgets: make the Recent Posts widget output '(no title)' for posts without a title.

Since WordPress 2.3, the Recent Posts widget used to output the post ID for posts
with an empty title. Using '(no title)' seems a best option and is consistent with
what's already used in other similar cases.

Props antonrinas, Ankit K Gupta.
Fixes #35709.

Built from https://develop.svn.wordpress.org/trunk@41149


git-svn-id: http://core.svn.wordpress.org/trunk@40989 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9-alpha-41148';
+$wp_version = '4.9-alpha-41149';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.

wp-includes/widgets/class-wp-widget-recent-posts.php

@@ -82,7 +82,7 @@ class WP_Widget_Recent_Posts extends WP_Widget {
 		<ul>
 		<?php while ( $r->have_posts() ) : $r->the_post(); ?>
 			<li>
-				<a href="<?php the_permalink(); ?>"><?php get_the_title() ? the_title() : the_ID(); ?></a>
+				<a href="<?php the_permalink(); ?>"><?php get_the_title() ? the_title() : _e( '(no title)' ); ?></a>
 			<?php if ( $show_date ) : ?>
 				<span class="post-date"><?php echo get_the_date(); ?></span>
 			<?php endif; ?>