[Search] Fixed empty search

Pressing enter on the searchbar before putting
any input would before hide the filtree when
it shouldn't. Now it does not.

platform/features/search/src/controllers/SearchController.js

@@ -44,7 +44,7 @@ define(function () {
             var inputText = $scope.ngModel.input;
             
             // Update whether the file tree should be displayed 
-            if (inputText === '') {
+            if (inputText === '' || inputText === undefined) {
                 $scope.ngModel.search = false;
             } else {
                 $scope.ngModel.search = true;