cros: Update saml banner text and style.

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. */
 }
 
 #gaia-signin.no-right-panel {
   width: 522px;
 }
 
 #gaia-signin.saml {
-  padding: 75px 10px 10px;
+  padding: 75px 0 0;

[bartfab (slow), 2014/01/29 15:29:38]

Nit: Would padding-top: 75px not be sufficient?

[xiyuan, 2014/01/29 16:12:34]

The top padding is space for logo and saml notice banner. It should be enough
for one-line banner text.

[bartfab (slow), 2014/01/29 16:30:17]

What I meant was whether |padding-top: 75px| would not be a sufficient and
equivalent CSS statement for exactly the same thing as |padding: 75px 0 0|. I
find the former easier to parse than the latter. But it was an optional nit
anyway.

[xiyuan, 2014/01/29 16:32:10]

Oh, we need the '0 0' to override the non-saml #gaia-signin's style at line 8.

[bartfab (slow), 2014/01/30 09:54:54]

Ah, good to know. Thanks for clarifying.

 }
 
 #signin-right {
   -webkit-margin-before: 80px;
   -webkit-margin-start: 30px;
   top: 60px;
   width: 200px;
 }
 
 #signin-right,
@@ skipping 121 matching lines @@
 
 #saml-notice-container {
   left: 0;
   position: absolute;
   right: 0;
   text-align: center;
   top: 50px;
 }
 
 #saml-notice-message {
-  background-color: rgb(250, 245, 202);
-  border: 2px solid rgb(250, 245, 202);
-  border-radius: 2px;
-  margin-left: auto;
-  margin-right: auto;
+  margin: 0 auto;
 }