Reduce webkit CSS prefixes in ui/ styles

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;
   background-color: black;
   font-size: 84%;
   margin: 0;
 }
@@ skipping 446 matching lines @@
   overflow: hidden;
   position: absolute;
   width: 100%;
 }
 
 .gallery .image-wrapper > img {
   position: absolute;
 }
 
 .gallery .image-wrapper > img:not(.cached) {
-  -webkit-animation: fadeIn 500ms ease-in;
+  animation: fadeIn 500ms ease-in;
 }
 
-@-webkit-keyframes fadeIn {
+@keyframes fadeIn {
   from {
     opacity: 0;
   }
   to {
     opacity: 1;
   }
 }
 
 .gallery .ribbon-image > .indicator {
-  -webkit-transition: opacity 500ms ease-in;
+  transition: opacity 500ms ease-in;

[Dan Beam, 2016/11/29 06:17:12]

alphabetize

[Eric Willigers, 2016/11/30 04:04:56]

Done.

   background-image: -webkit-image-set(
       url(../images/100/slide_view.png) 1x,
       url(../images/200/slide_view.png) 2x);
   background-position: center;
   background-repeat: no-repeat;
   height: 100%;
   opacity: 0;
   position: absolute;
   width: 100%;
 }
@@ skipping 932 matching lines @@
 .thumbnail-view .animation-thumbnail {
   background-repeat: no-repeat;
   background-size: cover;
   display: none;
   position: absolute;
 }
 
 .thumbnail-view .animation-thumbnail.animating {
   display: block;
 }