[DevTools] Show LastModified and ResponseTime of ServiceWorker script in DevTools

Source/devtools/front_end/ui/smallIcon.css

 /*
  * Copyright (c) 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.
  */
 
 div {
     width: 10px;
     height: 10px;
     margin-right: 2px;
     display: inline-block;
 }
 
 div.error-icon,
 div.warning-icon,
+div.info-icon,
 div.device-icon,
 div.red-ball,
 div.green-ball,
 div.orange-ball {
     background-image: url(Images/statusbarButtonGlyphs.png);
     background-size: 320px 144px;
 }
 
 @media (-webkit-min-device-pixel-ratio: 1.5) {
 div.error-icon,
 div.warning-icon,
+div.info-icon,
 div.device-icon,
 div.red-ball,
 div.green-ball,
 div.orange-ball {
     background-image: url(Images/statusbarButtonGlyphs_2x.png);
 }
 } /* media */
 
 div.error-icon {
     background-position: -213px -96px;
 }
 
 div.warning-icon {
     background-position: -202px -107px;
 }
 
+div.info-icon {
+    background-position: -213px -107px;
+}
+
 div.device-icon {
     background-position: -224px -107px;
 }
 
 div.red-ball {
     background-position: -224px -96px;
 }
 
 div.green-ball {
     background-position: -235px -96px;
 }
 
 div.orange-ball {
     background-position: -246px -96px;
 }