Add controlled setting indicators for content settings

chrome/browser/resources/options/content_settings.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. */
 
 #content-settings-page {
-  min-width: 600px;
+  min-width: 620px;
 }
 
 #content-settings-exceptions-area {
   min-width: 540px;
 }
 
 .exception-pattern {
   -webkit-box-flex: 1;
   -webkit-margin-end: 10px;
   -webkit-margin-start: 14px;
@@ skipping 34 matching lines @@
   margin-bottom: 10px;
   margin-top: 4px;
 }
 
 #disable-plugins-container {
   /* Same as .checkbox and .radio padding. Using padding instead of margin
    * to ensure minimum height for tap target. */
   padding: 7px 0;
 }
 
-div[role='listitem'][managedby] {
+div[role='listitem'][controlled-by] {
   color: #666;
   font-style: italic;
   position: relative;
 }
 
-.settings-list div[role='listitem'][managedby='policy'],
-.settings-list div[role='listitem'][managedby='extension'] {
-  background: -webkit-linear-gradient(rgb(250, 230, 146), rgb(250, 230, 146));
+.settings-list div[role='listitem'][controlled-by='policy'],
+.settings-list div[role='listitem'][controlled-by='extension'] {
+  background: rgb(250, 230, 146);
   border-bottom: 1px solid rgb(201, 189, 141);
   border-top: 0;
 }
 
-list div[role='listitem'][managedby='policy'] .close-button {
-  background-image: url('chrome://theme/IDR_MANAGED');
-  background-size: 16px;
-  opacity: 1;
-}
-
-list div[role='listitem'][managedby='extension'] .close-button {
-  background-image: url('chrome://theme/IDR_EXTENSIONS_SECTION_SMALL');
-  background-size: 16px;
-  opacity: 1;
-}
-
 .sublabel {
   -webkit-margin-start: 2em;
 }