Remove webkit prefixes for CSS Animation in chrome/ styles

chrome/browser/resources/hotword_audio_verification/style.css

 /* Copyright 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. */
 
 /* TODO(xdai): Remove hard-coded font-family for 'Roboto'. */
 
 * {
   box-sizing: border-box;
   color: rgba(0, 0, 0, .54);
   font-family: Roboto, 'Noto Sans', sans-serif;
@@ skipping 156 matching lines @@
   display: inline-block;
   line-height: 13px;
   padding-top: 3px;
   vertical-align: top;
 }
 
 .train.recorded .text {
   color: rgba(66, 133, 244, 1);
 }
 
-@-webkit-keyframes rotate {
+@keyframes rotate {
   from { transform: rotate(0); }
   to { transform: rotate(359deg); }
 }
 
 .train.listening .icon {
-  -webkit-animation: rotate 2s linear infinite;
+  animation: rotate 2s linear infinite;
   background: -webkit-image-set(
       url(../images/placeholder-loader-1x.png) 1x,
       url(../images/placeholder-loader-2x.png) 2x)
       no-repeat;
 }
 
 .train.not-started .icon {
   background: -webkit-image-set(
       url(../images/ic-check-gray-1x.png) 1x,
       url(../images/ic-check-gray-2x.png) 2x)
@@ skipping 89 matching lines @@
 
 .buttonbar .message .icon {
   display: inline-block;
   height: 18px;
   margin-right: 8px;
   vertical-align: top;
   width: 18px;
 }
 
 .buttonbar .message.wait .icon {
-  -webkit-animation: rotate 2s linear infinite;
+  animation: rotate 2s linear infinite;
   background: -webkit-image-set(
       url(../images/placeholder-loader-1x.png) 1x,
       url(../images/placeholder-loader-2x.png) 2x)
       no-repeat;
 }
 
 .buttonbar .message.error .icon {
   background: -webkit-image-set(
       url(../images/ic-error-1x.png) 1x,
       url(../images/ic-error-2x.png) 2x)
@@ skipping 48 matching lines @@
   background: none;
   border: none;
   color: rgb(58, 218, 255);
   float: right;
   height: 32px;
   margin-left: 18px;
   min-width: 56px;
   padding: 0 8px 0 8px;
   text-transform: uppercase;
 }