DevTools: only allow status bar items in status bars.

Source/devtools/front_end/resources/FileSystemView.js

Index: Source/devtools/front_end/resources/FileSystemView.js
diff --git a/Source/devtools/front_end/resources/FileSystemView.js b/Source/devtools/front_end/resources/FileSystemView.js
index 8a92d16ce9206c39149cb3ef30678cdbf065377e..097f2b0d28c7059f9449bcf84aa62217d44310d1 100644
--- a/Source/devtools/front_end/resources/FileSystemView.js
+++ b/Source/devtools/front_end/resources/FileSystemView.js
@@ -60,11 +60,11 @@ WebInspector.FileSystemView = function(fileSystem)
 
 WebInspector.FileSystemView.prototype = {
     /**
-     * @type {!Array.<!Element>}
+     * @return {!Array.<!WebInspector.StatusBarItem>}
      */
-    get statusBarItems()
+    statusBarItems: function()
     {
-        return [this._refreshButton.element, this._deleteButton.element];
+        return [this._refreshButton, this._deleteButton];
     },
 
     /**