Gallery: replace paper-input of rename field with HTMLInputElement.

ui/file_manager/gallery/css/gallery.css

 /* Copyright (c) 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. */
 
 body {
   -webkit-user-select: none;
   font-size: 84%;
   margin: 0;
 }
 
@@ skipping 298 matching lines @@
   opacity: 0.2;
 }
 
 /* Filename */
 
 .filename-spacer {
   -webkit-margin-start: 16px;
   flex: 1 0 auto;
 }
 
-.filename-spacer paper-input {
+#rename-input {
   margin: 8px 0;
   min-width: 160px;
+  padding: 4px 0;
   width: -webkit-fit-content;
 }
 
-.filename-spacer paper-input::shadow paper-input-container {
-  padding: 4px 0;
+#rename-input > input {
+  color: white;
 }
 
 /* Bubble */
 
 .gallery .toolbar .bubble {
   bottom: 65px;
   font-size: 85%;
   left: 50px;
   position: absolute;
   width: 220px;
@@ skipping 1045 matching lines @@
 .thumbnail-view .animation-thumbnail {
   background-repeat: no-repeat;
   background-size: cover;
   display: none;
   position: absolute;
 }
 
 .thumbnail-view .animation-thumbnail.animating {
   display: block;
 }