MD Downloads: wrap some <paper-buttons>s in <template is="dom-if">

chrome/browser/resources/md_downloads/item.css

 /* Copyright 2015 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. */
 
 :host {
   display: flex;
   margin: 24px 0;
 }
 
 :host([hide-date]) {
@@ skipping 133 matching lines @@
 .dangerous #description {
   color: rgb(239, 108, 0);
 }
 
 #progress {
   --paper-progress-active-color: rgb(54, 126, 237);
   --paper-progress-container-color: rgb(223, 222, 223);
   width: auto;
 }
 
-#content:not(.show-progress) #progress {
-  display: none;
-}
-
 .controls {
   -webkit-margin-start: -8px;
 }
 
 #cancel,
 #retry,
 .keep,
 .discard {
   color: #5a5a5a;
 }
@@ skipping 46 matching lines @@
   #content {
     margin: 0 auto;
   }
 
   #date-container {
     flex: none !important;
     margin: 0 auto 16px;
     width: var(--downloads-item-width);
   }
 }