ChromeOS: Update Welcome screen material design OOBE.

chrome/browser/resources/chromeos/login/oobe_welcome.css

 /* Copyright 2016 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. */
 
-/************* Welcome Screen **************/
-#welcomeScreen #welcomeIllustration {
-  height: max-content;
-  width: max-content;
-}
-
-#welcomeScreen #welcomeNextButton {
-  padding-top: 32px;
-}
-
-#welcomeScreen #welcomeButtons {
-  font-size: 16px;
-  padding-top: 24px;
-}
-
-#welcomeScreen .buttonbox-text {
-  align-self: center;
-  color: rgba(0, 0, 0, 0.54);
-  font: 16px Roboto, sans-serif;
-  /* TODO(alemate): max-width should depend on Timezone visibility. */
-  max-width: 220px;
-  padding-top: 32px;
-  position: absolute;
-  text-align: center;
-  top: 32px;
-  width: max-content;
-}
-
-#welcomeScreen .action-icon {
-  --iron-icon-height: 32px;
-  --iron-icon-width: 32px;
-}
-
-#welcomeScreen .action-icon-spacer {
-  margin: 0;
-  padding: 0;
-  width: 218px;
-}
-
 /************* Language Screen **************/
 #languageScreen .language-selection-entry {
   border-top: 1px solid lightgrey;
   height: 44px;
   padding: 0 20px;
 }
 
 #languageScreen .language-selection-entry:last-of-type {
   border-bottom: 1px solid lightgrey;
 }
 
 #languageScreen .language-selection-title {
   color: rgba(0, 0, 0, 0.87);
   font: 13px Roboto, sans-serif;
 }
 
 /************* Accessibility Screen **************/
 #accessibilityScreen oobe-a11y-option {
   border-top: 1px solid lightgrey;
   min-height: 56px;
 }
 
 #accessibilityScreen oobe-a11y-option:last-of-type {
   border-bottom: 1px solid rgba(0, 0, 0, 0.14);
 }