Hand cursor on hover close & back buttons

chrome/browser/resources/chromeos/login/screen_gaia_signin.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.
  */
 
 #gaia-signin {
   height: 609px; /* Should be the same as #user-image.loading min-heigth. */
   padding: 70px 17px 69px;    /* Screen has no controls. */
   width: 722px; /* Should be the same as #user-image.loading width. */
 }
@@ skipping 82 matching lines @@
 }
 
 .loading.auth-completed #close-button-item {
   display: none;
 }
 
 #close-button-item:disabled {
   background-image: url(chrome://theme/IDR_LOGIN_CLOSE_BUTTTON_MASKED);
 }
 
+#close-button-item:hover {
+  cursor: pointer;
+}
+
 #back-button-item {
   background: transparent none;
   background-image: url(chrome://theme/IDR_LOGIN_BACK_BUTTTON);
   background-position: center;
   background-repeat: no-repeat;
   height: 18px;
   left: 14px;
   position: absolute;
   top: 14px;
   width: 18px;
   z-index: 1;
 }
 
 html[dir=rtl] #back-button-item {
   -webkit-transform: scaleX(-1);
   left: auto;
   right: 14px;
 }
 
 .new-gaia-flow .full-width #back-button-item {
   display: none;
 }
 
 #back-button-item:disabled {
   background-image: url(chrome://theme/IDR_LOGIN_BACK_BUTTTON_MASKED);
 }
 
+#back-button-item:hover {
+  cursor: pointer;
+}
+
 .signin-text {
   color: #666;
   margin-top: 20px;
 }
 
 .signin-link {
   color: rgb(37, 79, 155);
   cursor: pointer;
   text-decoration: none;
 }
@@ skipping 167 matching lines @@
 
 html /deep/ #forgotPasswordDlg {
   position: fixed;
   top: 200px;
   width: 350px;
 }
 
 html /deep/ #forgotPasswordDlg gaia-paper-button[autofocus] {
   color: rgb(66, 133, 244);
 }