Print Preview: Display a throbber when the user requests the system print

chrome/browser/resources/print_preview/print_preview.html

Index: chrome/browser/resources/print_preview/print_preview.html
diff --git a/chrome/browser/resources/print_preview/print_preview.html b/chrome/browser/resources/print_preview/print_preview.html
index 8bf4469fc4c9db12ec66133f4d9601ce43d1d38e..423f98b3c3e5a058f415817847fe2f5ba52f4de4 100644
--- a/chrome/browser/resources/print_preview/print_preview.html
+++ b/chrome/browser/resources/print_preview/print_preview.html
@@ -5,6 +5,7 @@
 <title i18n-content="title"></title>
 <link rel="icon" href="../../../app/theme/print_preview_favicon.png">
 <link rel="stylesheet" href="../webui.css">
+<link rel="stylesheet" href="chrome://resources/css/throbber.css">
 <link rel="stylesheet" href="print_preview.css">
 <script src="chrome://resources/js/local_strings.js"></script>
 <script src="chrome://resources/js/cr.js"></script>
@@ -105,8 +106,10 @@
       </div>
       <hr>
       <div id="system-dialog-div">
-        <a id="system-dialog-link" href="#"
-            i18n-content="systemDialogOption"></a>
+        <button id="system-dialog-link" class="link-button"
+            i18n-content="systemDialogOption"></button>
+        <!-- TODO(dpapad): Investigate whey hidden attribute does not work. -->
+        <div id="system-dialog-throbber" class="throbber hidden"></div>
       </div>
     </div>
   </div>
@@ -124,6 +127,6 @@
     </div>
   </div>
   <object id="dummy-viewer" type="application/pdf"
-      src="chrome://print/dummy.pdf"/>
+      src="chrome://print/dummy.pdf"></object>
 </body>
 </html>