[DevTools] Don't select anything when no items in FilteredItemSelectionDialog.

Source/devtools/front_end/sources/FilteredItemSelectionDialog.js

Index: Source/devtools/front_end/sources/FilteredItemSelectionDialog.js
diff --git a/Source/devtools/front_end/sources/FilteredItemSelectionDialog.js b/Source/devtools/front_end/sources/FilteredItemSelectionDialog.js
index e0558bbaf64925890dd4472c6149223c1cd6122f..495f4de4199bbab083aae462b1926ee37d509f4f 100644
--- a/Source/devtools/front_end/sources/FilteredItemSelectionDialog.js
+++ b/Source/devtools/front_end/sources/FilteredItemSelectionDialog.js
@@ -325,6 +325,8 @@ WebInspector.FilteredItemSelectionDialog.prototype = {
      */
     _updateSelection: function(index, makeLast)
     {
+        if (!this._filteredItems.length)
+            return;
         var element = this._viewportControl.renderedElementAt(this._selectedIndexInFiltered);
         if (element)
             element.classList.remove("selected");