Add a button to clear local storage for a given origin to Website Settings dialog.

chrome/browser/resources/options/website_settings.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. */
 
 #website-settings-page {
   max-height: 445px;
   min-width: 540px;
 }
 
 #website-settings-edit-page {
@@ skipping 46 matching lines @@
 
 #website-settings-permission-column {
   -webkit-margin-start: 8px;
 }
 
 .website-properties {
   -webkit-margin-after: 8px;
   -webkit-margin-start: 8px;
 }
 
-.website-property {
+.website-property-area {
   -webkit-margin-after: 22px;
+  align-items: center;
+  display: flex;
+  justify-content: space-between;
+}
+
+.website-property-button {
+  -webkit-margin-after: 9em;
 }
 
 #website-title {
   -webkit-margin-after: 22px;
   -webkit-margin-before: 0;
   -webkit-padding-start: 21px;
   font-size: 15px;
   line-height: 20px;
 }
 
@@ skipping 43 matching lines @@
   -webkit-padding-start: 21px;
   font-size: 13px;
 }
 
 .permission-option {
   -webkit-margin-before: 4px;
   align-items: center;
   display: flex;
   justify-content: space-between;
 }