[ServiceWorker] Cache inspector out from flag, style & icon changes

Source/devtools/front_end/resources/serviceWorkerCacheViews.css

 /*
  * Copyright 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.
  */
 
 .service-worker-cache-data-view .data-view-toolbar {
     position: relative;
     background-color: #eee;
     border-bottom: 1px solid #ccc;
@@ skipping 18 matching lines @@
 }
 
 .service-worker-cache-data-view .data-grid .data-container tr:nth-last-child(1) {
     background-color: white;
 }
 
 .service-worker-cache-data-view .data-grid .data-container tr:nth-last-child(1) td {
     border: 0;
 }
 
+.service-worker-cache-data-view .data-grid .data-container tr:nth-last-child(2) td {
+    border-bottom: 1px solid #aaa;
+}
+
 .service-worker-cache-data-view .section,
 .service-worker-cache-data-view .section > .header,
 .service-worker-cache-data-view .section > .header .title {
     margin: 0;
     min-height: inherit;
     line-height: inherit;
 }
 
 .service-worker-cache-data-view .primitive-value {
     padding-top: 1px;
 }
 
 .service-worker-cache-data-view .data-grid .data-container td .section .header .title {
     white-space: nowrap;
     text-overflow: ellipsis;
     overflow: hidden;
 }