[MD History] Disable Clear Browsing Data button for supervised users.

chrome/browser/resources/md_history/side_bar.js

 // Copyright 2016 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.
 
 Polymer({
   is: 'history-side-bar',
 
   behaviors: [Polymer.IronA11yKeysBehavior],
 
   properties: {
     selectedPage: {
       type: String,
       notify: true,
     },
 
     showFooter: Boolean,

[Dan Beam, 2017/02/02 07:43:11]

nit: this could be a property instead?

deletingAllowed_: {
  type: Boolean,
  value: function() {
    return loadTimeData.getBoolean('allowDeletingHistory');
  },
},

[tsergeant, 2017/02/03 00:34:50]

Seems like a better pattern -- we should probably do this in item.html/js as
well.

[calamity, 2017/02/07 05:08:58]

Done.

   },
 
   keyBindings: {
     'space:keydown': 'onSpacePressed_',
   },
 
   /**
    * @param {CustomEvent} e
    * @private
    */
@@ skipping 22 matching lines @@
   },
 
   /**
    * Prevent clicks on sidebar items from navigating. These are only links for
    * accessibility purposes, taps are handled separately by <iron-selector>.
    * @private
    */
   onItemClick_: function(e) {
     e.preventDefault();
   },
+
+  /**
+   * If the user is a supervised user the delete button is not shown.
+   * @private
+   */
+  deletingAllowed_: function() {
+    return loadTimeData.getBoolean('allowDeletingHistory');
+  },
 });