[DevTools] Don't update Object Event Listeners sidebar when hidden

Source/devtools/front_end/sources/ObjectEventListenersSidebarPane.js

Index: Source/devtools/front_end/sources/ObjectEventListenersSidebarPane.js
diff --git a/Source/devtools/front_end/sources/ObjectEventListenersSidebarPane.js b/Source/devtools/front_end/sources/ObjectEventListenersSidebarPane.js
index bdc30fc1ef485db7cdc82991ea7a48eb71b80851..30383c563e6187ff4e8a3727a5c442f01763efe9 100644
--- a/Source/devtools/front_end/sources/ObjectEventListenersSidebarPane.js
+++ b/Source/devtools/front_end/sources/ObjectEventListenersSidebarPane.js
@@ -11,11 +11,11 @@ WebInspector.ObjectEventListenersSidebarPane = function()
     WebInspector.SidebarPane.call(this, "Event Listeners");
     this.element.classList.add("event-listeners-sidebar-pane");
 
-    var refreshButton = new WebInspector.ToolbarButton(WebInspector.UIString("Refresh"), "refresh-toolbar-item");
-    refreshButton.addEventListener("click", this._refreshClick.bind(this));
-    this.toolbar().appendToolbarItem(refreshButton);
+    this._refreshButton = new WebInspector.ToolbarButton(WebInspector.UIString("Refresh"), "refresh-toolbar-item");
+    this._refreshButton.addEventListener("click", this._refreshClick.bind(this));
+    this._refreshButton.setEnabled(false);
+    this.toolbar().appendToolbarItem(this._refreshButton);
 
-    WebInspector.context.addFlavorChangeListener(WebInspector.ExecutionContext, this.update, this);
     this._eventListenersView = new WebInspector.EventListenersView(this.element);
 }
 
@@ -38,12 +38,21 @@ WebInspector.ObjectEventListenersSidebarPane.prototype = {
         Promise.all([this._windowObjectInContext(executionContext)]).then(this._eventListenersView.addObjects.bind(this._eventListenersView));
     },
 
-    expand: function()
+    wasShown: function()
     {
-        WebInspector.SidebarPane.prototype.expand.call(this);
+        WebInspector.SidebarPane.prototype.wasShown.call(this);
+        WebInspector.context.addFlavorChangeListener(WebInspector.ExecutionContext, this.update, this);
+        this._refreshButton.setEnabled(true);
         this.update();
     },
 
+    willHide: function()
+    {
+        WebInspector.SidebarPane.prototype.willHide.call(this);
+        WebInspector.context.removeFlavorChangeListener(WebInspector.ExecutionContext, this.update, this);
+        this._refreshButton.setEnabled(false);
+    },
+
     /**
      * @param {!WebInspector.ExecutionContext} executionContext
      * @return {!Promise<!WebInspector.RemoteObject>} object