Ticket #28587: 28587.2.patch

src/wp-admin/js/theme.js

@@ -190 +190 @@
                         return match.test( haystack );
                 });
 
+                if ( results.length === 0 ) {
+                        this.trigger( 'query:empty' );
+                } else {
+                        $( 'body' ).removeClass( 'no-results' );
+                }
+
                 this.reset( results );
         },
 

src/wp-admin/themes.php

@@ -233 +233 @@
 </div>
 <div class="theme-overlay"></div>
 
+<p class="no-themes"><?php _e( 'No themes found. Try a different search.' ); ?></p>
+
 <?php
 // List broken themes, if any.
 if ( ! is_multisite() && current_user_can('edit_themes') && $broken_themes = wp_get_themes( array( 'errors' => true ) ) ) {