Creates GCP promo for ChromeOS users with no cloud printers.

chrome/browser/resources/print_preview/print_preview.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. */
 
 html {
   height: 100%;
 }
 
 body {
   display: -webkit-box;
@@ skipping 262 matching lines @@
 
 #print-preview .button-strip button {
   -webkit-margin-start: 4px;
   display: block;
 }
 
 #link-container {
   -webkit-box-orient: vertical;
   display: -webkit-box;
 }
+
+#main-container {
+  -webkit-box-flex: 1;
+  -webkit-box-orient: vertical;
+  display: -webkit-box;
+  height: 100%;
+  position: relative;
+}