Devtools: Add new row in toolbarButtonGlyphs and layout editor icon

Source/devtools/front_end/ui/softContextMenu.css

 /*
  * Copyright (c) 2014 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.
  */
 
 :host {
     position: absolute;
     border: 1px solid rgba(196, 196, 196, 0.9);
     border-top: 1px solid rgba(196, 196, 196, 0.5);
@@ skipping 71 matching lines @@
     text-align: right;
     padding-left: 10px;
 }
 
 .soft-context-menu-item-mouse-over .soft-context-menu-shortcut {
     color: inherit;
 }
 
 .checkmark {
     background-image: url(Images/toolbarButtonGlyphs.png);
-    background-size: 352px 144px;
+    background-size: 352px 168px;
     opacity: 0.7;
     width: 10px;
     height: 10px;
     background-position: -128px -109px;
     display: inline-block;
     pointer-events: none;
     margin: auto 5px auto 0px;
 }
 
 @media (-webkit-min-device-pixel-ratio: 1.5) {
 .checkmark {
     background-image: url(Images/toolbarButtonGlyphs_2x.png);
 }
 }