[Extensions Page] Fix the flicker of "No extensions" before extension data loads

chrome/browser/resources/extensions/extensions.css

 /* Copyright (c) 2012 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. */
 
 html.loading * {
   transition-duration: 0ms !important;
 }
 
 html:not(.focus-outline-visible)
 :enabled:focus:-webkit-any(input[type='checkbox'], input[type='radio']) {
@@ skipping 123 matching lines @@
 /* Contents */
 
 #extension-settings {
   max-width: 738px;
 }
 
 #no-extensions-message {
   font-weight: bold;
 }
 
+#no-extensions {
+  margin-top: 3em;
+}
+
 #suggest-gallery {
   -webkit-padding-start: 10px;
 }
 
 #footer-section {
   background: url(chrome://theme/IDR_WEBSTORE_ICON_32) no-repeat left center;
   background-size: 32px 32px;
   font-size: 1.25em;
 }
 
 html[dir=rtl] #footer-section {
   background: url(chrome://theme/IDR_WEBSTORE_ICON_32) no-repeat right center;
 }
 
 #footer-section > a {
   -webkit-margin-start: 42px;
   line-height: 32px;
 }
 
-.empty-extension-list {
-  height: 3em;
-}
-
-.loading #no-extensions,
-.loading #footer-section,
-#extension-settings-list:not(.empty-extension-list) ~ #no-extensions,
-.empty-extension-list ~ #footer-section {
-  display: none;
-}
-
 .extension-list-item-wrapper {
   margin: 23px 0;
 }
 
 .extension-list-item {
   background-repeat: no-repeat;
   display: -webkit-box;
   min-height: 48px;
 }
 
@@ skipping 226 matching lines @@
 /* Sideload Wipeout */
 
 .sideload-wipeout-learn-more {
   text-decoration: none;
 }
 
 .sideload-wipeout-banner .page-banner-text {
   -webkit-padding-start: 8px;
   background-image: none;
 }