extensions: darken some disabled text for better contrast.

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 * {
   -webkit-transition-duration: 0 !important;
 }
 
 html:not(.focus-outline-visible)
 :enabled:focus:-webkit-any(input[type='checkbox'], input[type='radio']) {
@@ skipping 229 matching lines @@
   -webkit-padding-end: 7px;
   -webkit-padding-start: 55px;
 }
 
 .extension-description,
 .extension-version,
 .extension-list-item-wrapper.inactive-extension .extension-details,
 .location-text,
 .blacklist-text,
 .enable-checkbox input:disabled + .enable-checkbox-text {
-  color: rgb(151, 156, 160);
+  color: rgb(115, 119, 122);
 }
 
 .enable-controls {
   /* Matches right: position of dev controls toggle. */
   -webkit-margin-end: 20px;
   position: relative;
 }
 
 /* We use x[is='action-link'] here so that we get higher specifity than the
  * action link rules without resorting to the Dark Side (!IMPORTANT). */
@@ skipping 156 matching lines @@
 /* Sideload Wipeout */
 
 .sideload-wipeout-learn-more {
   text-decoration: none;
 }
 
 .sideload-wipeout-banner .page-banner-text {
   -webkit-padding-start: 8px;
   background-image: none;
 }