Control whether a filter editor should be rendered via setVisible()

We (may) have situations where a controller or view has to access the filter editor being created via Controller::setupFilterControl().
This is impossible if the view is compact because the filterEditor will be unset. This change introduces FilterEditor::setVisible() for
giving the responsibility of rendering to the filter editor. Controller::setupFilterControl() will be adapted accordingly.

refs #10778

library/Icinga/Web/Widget/FilterEditor.php

@@ -55,6 +55,13 @@ class FilterEditor extends AbstractWidget
      */
     private $selectedIdx;
 
+    /**
+     * Whether the filter control is visible
+     *
+     * @var bool
+     */
+    protected $visible = true;
+
     /**
      * Create a new FilterWidget
      *
@@ -144,6 +151,30 @@ class FilterEditor extends AbstractWidget
         return $this;
     }
 
+    /**
+     * Get whether the filter control is visible
+     *
+     * @return  bool
+     */
+    public function isVisible()
+    {
+        return $this->visible;
+    }
+
+    /**
+     * Set whether the filter control is visible
+     *
+     * @param   bool    $visible
+     *
+     * @return  $this
+     */
+    public function setVisible($visible)
+    {
+        $this->visible = (bool) $visible;
+
+        return $this;
+    }
+
     protected function redirectNow($url)
     {
         $response = Icinga::app()->getFrontController()->getResponse();
@@ -731,6 +762,9 @@ class FilterEditor extends AbstractWidget
 
     public function render()
     {
+        if (! $this->visible) {
+            return '';
+        }
         if (! $this->preservedUrl()->getParam('modifyFilter')) {
             return '<div class="filter">' . $this->renderSearch() . $this->view()->escape($this->shorten($this->filter, 50)) . '</div>';
         }