Migrate <cr-dialog> from PaperDialogBehavior to native <dialog>.

chrome/browser/resources/md_history/list_container.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-list-container',
 
   properties: {
     // The path of the currently selected page.
     selectedPage_: String,
@@ skipping 79 matching lines @@
   },
 
   /**
    * Delete all the currently selected history items. Will prompt the user with
    * a dialog to confirm that the deletion should be performed.
    */
   deleteSelectedWithPrompt: function() {
     if (!loadTimeData.getBoolean('allowDeletingHistory'))
       return;
 
-    this.$.dialog.open();
+    this.$.dialog.showModal();
   },
 
   /**
    * @param {HistoryRange} range
    * @private
    */
   groupedRangeChanged_: function(range) {
     this.selectedPage_ = this.queryState.range == HistoryRange.ALL_TIME ?
       'infinite-list' : 'grouped-list';
 
@@ skipping 73 matching lines @@
         .then(function(items) {
           this.$['infinite-list'].removeDeletedHistory_(items);
           // This unselect-all is to reset the toolbar when deleting a selected
           // item. TODO(tsergeant): Make this automatic based on observing list
           // modifications.
           this.fire('unselect-all');
         }.bind(this));
     menu.closeMenu();
   },
 });