DevTools: [Persistence] implement automapping

third_party/WebKit/Source/devtools/front_end/settings/editFileSystemView.css

 /*
  * Copyright 2015 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 .file-system-header {
     display: flex;
     flex-direction: row;
     align-items: center;
@@ skipping 14 matching lines @@
 .file-system-list {
     flex: auto;
 }
 
 .file-system-list-empty {
     flex: auto;
     height: 30px;
     display: flex;
     align-items: center;
     justify-content: center;
+    text-align: center;
 }
 
 .file-system-list-item {
     padding: 3px 5px 3px 5px;
     height: 30px;
     display: flex;
     align-items: center;
     flex: auto 1 1;
 }
 
@@ skipping 36 matching lines @@
     visibility: hidden;
 }
 
 .file-system-locked:after {
     content: "\1F512";
 }
 
 .file-system-list-item.locked .file-system-locked {
     visibility: visible;
 }