Devtools: Add new row in toolbarButtonGlyphs and layout editor icon

Source/devtools/front_end/audits/auditResultTree.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.
  */
 
 .severity {
     background-image: url(Images/toolbarButtonGlyphs.png);
-    background-size: 352px 144px;
+    background-size: 352px 168px;
     display: inline-block;
     width: 10px;
     height: 10px;
     position: relative;
     top: 1px;
     margin-right: 4px;
 }
 
 li {
     -webkit-user-select: text;
@@ skipping 12 matching lines @@
 .severity.warning {
     background-position: -246px -96px;
 }
 
 .severity.info {
     background-position: -235px -96px;
 }
 .audit-result {
     font-weight: bold;
 }