Split the Website Settings page's origin list into Allowed and Blocked lists.

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 {
   max-height: 445px;
   min-width: 540px;
 }
 
 .website-column-headers {
   padding: 3px 0 6px;
@@ skipping 89 matching lines @@
 
 #website-settings-edit-page .website-property-button {
   min-width: 70px;
 }
 
 #website-settings-edit-page .website-property-controls {
   min-width: 165px;
 }
 
 /* Styles for the origin list elements in the website settings page. */
-#origin-list {
+.origin-list {
   border: 1px solid #d9d9d9;
   font-size: 13px;
+  height: 192px;
   margin: 5px 0 0;
-  min-height: 287px;
+}
+
+#website-settings-page .blocked-origin-list {
+  height: 128px;
+  min-height: 128px;
+}
+
+#website-settings-page .nonsplit-origin-list {
+  height: 357px;
+  min-height: 357px;
 }
 
 #origin-list-item {
   height: 30px;
 }
 
 .local-storage-usage {
   color: #7f7f7f;
   margin: auto 0;
 }
 
 list.origin-list .favicon-cell {
   -webkit-margin-start: 6px;
   -webkit-padding-start: 21px;
 }
 
 list.origin-list .favicon-cell {
   -webkit-margin-start: 5px;
   -webkit-padding-start: 21px;
   font-size: 13px;
 }
 
 .permission-option {
   -webkit-margin-before: 4px;
   align-items: center;
   display: flex;
   justify-content: space-between;
 }