DevTools: Fix Elements tab event listener removal

third_party/WebKit/Source/devtools/front_end/components/EventListenersView.js

Index: third_party/WebKit/Source/devtools/front_end/components/EventListenersView.js
diff --git a/third_party/WebKit/Source/devtools/front_end/components/EventListenersView.js b/third_party/WebKit/Source/devtools/front_end/components/EventListenersView.js
index 8f57990943d15f6b358869e5a552a55e21e8b6a8..dd9804b79ed3adfad527ed5893a86e835ee79d5b 100644
--- a/third_party/WebKit/Source/devtools/front_end/components/EventListenersView.js
+++ b/third_party/WebKit/Source/devtools/front_end/components/EventListenersView.js
@@ -326,10 +326,8 @@ Components.ObjectEventListenerBar = class extends TreeElement {
   _removeListenerBar() {
     var parent = this.parent;
     parent.removeChild(this);
-    if (!parent.childCount()) {
-      parent.parent.removeChild(parent);
-      return;
-    }
+    if (!parent.childCount())
+      parent.collapse();
     var allHidden = true;
     for (var i = 0; i < parent.childCount(); ++i) {
       if (!parent.childAt(i).hidden)