navigation MDL-22072 Icons are no longer shown on the navigation bar by default.

lib/navigationlib.php

@@ -122,6 +122,8 @@ class navigation_node implements renderable {
     public $forcetitle = false;
     /** @var navigation_node A reference to the node parent */
     public $parent = null;
+    /** @var bool Override to not display the icon even if one is provided **/
+    public $hideicon = false;
     /** @var array */
     protected $namedtypes = array(0=>'system',10=>'category',20=>'course',30=>'structure',40=>'activity',50=>'resource',60=>'custom',70=>'setting', 80=>'user');
     /** @var moodle_url */

lib/outputrenderers.php

@@ -2067,6 +2067,7 @@ END;
         $htmlblocks = array();
         // Iterate the navarray and display each node
         foreach ($items as $item) {
+            $item->hideicon = true;
             $htmlblocks[] = html_writer::tag('li', $this->render($item));
         }
 
@@ -2077,7 +2078,7 @@ END;
     protected function render_navigation_node(navigation_node $item) {
         $content = $item->get_content();
         $title = $item->get_title();
-        if ($item->icon instanceof renderable) {
+        if ($item->icon instanceof renderable && !$item->hideicon) {
             $icon = $this->render($item->icon);
             $content = $icon.' '.$content; // use CSS for spacing of icons
         }