[File Manager] Support HiDPI images in action picker and default action picker

chrome/browser/resources/file_manager/css/file_manager.css

 /* Copyright (c) 2012 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. */
 
 html.col-resize * {
   cursor: col-resize !important;
 }
 
 /* Outer frame of the dialog. */
 body {
@@ skipping 633 matching lines @@
 }
 
 /* Padding counterweights negative margins of items, thus eliminating scroll
    bar when it's not needed. Max height is set to fit 8 items before showing
    scroll bar. */
 #default-actions-list {
   max-height: 328px;
   padding: 1px 0;
 }
 
-#default-actions-list > li {
-  display: -webkit-box;
+#default-actions-list > li > * {
+  background-position: 5px center;
+  background-repeat: no-repeat;
+  background-size: 16px 16px;
+  padding-left: 26px;
 }
 
-#default-actions-list > li > * {
-  display: block;
-  padding: 0 5px;
-}
-
-#default-actions-list > li > img {
-  height: 16px;
-  padding-top: 12px;
-}
-
-
 #list-container list > *,
 #list-container grid > *,
 #default-actions-list > * {
   background-image: none;
   border-radius: 0;
   line-height: 30px;
 }
 
 #list-container list > [selected],
 #list-container grid > [selected],
@@ skipping 727 matching lines @@
   width: 50%;
 }
 
 #list-container .table-header-inner {
   height: 100%;
 }
 
 #list-container .table-header-cell:hover {
   background-color: #f2f2f2;
 }