Provide a link to restart chrome when changing gpu settings

chrome/browser/resources/options/browser_options.js

Index: chrome/browser/resources/options/browser_options.js
===================================================================
--- chrome/browser/resources/options/browser_options.js	(revision 189066)
+++ chrome/browser/resources/options/browser_options.js	(working copy)
@@ -467,6 +467,17 @@
         }
       }
 
+      // System section.
+      if (!cr.isChromeOS) {
+        $('gpu-mode-reset-restart').style.visibility = 'hidden';

[Dan Beam, 2013/03/21 02:03:52]

you should change this to .hidden = true;

[Zhenyao Mo, 2013/03/21 21:52:53]

Done.

+        $('gpu-mode-checkbox').onclick = function(event) {

[Dan Beam, 2013/03/21 02:03:52]

it seems the code as it is now is slightly suboptimal as if you double click
this it'll still show "restart now".  something like:

$('gpu-mode-checkbox').onchange = function(event) {
  $('gpu-mode-reset-restart').hidden =
      event.currentTarget.checked == theCurrentValue;
};

might make it so that the "restart" link is only showing when you actually need
to restart...

[Zhenyao Mo, 2013/03/21 21:52:53]

This is more complicated.  Because a user can modify the setting then navigate
to another page and come back, or open a second settings page.  So we need to
query the current state from chrome instead of replying on a local variable. 
I'd like to do that in a separate CL.

[Dan Beam, 2013/03/21 22:19:27]

pref notifications should change the checkbox already if you check/uncheck from
a different place, right?

+          $('gpu-mode-reset-restart').style.visibility = 'visible';

[Dan Beam, 2013/03/21 02:03:52]

and .hidden = false; to avoid invisible text causing wrapping

[Zhenyao Mo, 2013/03/21 21:52:53]

Done.

+        };
+        $('gpu-mode-reset-restart-link').onclick = function(event) {

[Dan Beam, 2013/03/21 02:03:52]

event.preventDefault();

[Zhenyao Mo, 2013/03/21 21:52:53]

Done.

+          chrome.send('restartBrowser');
+        };
+      }
+
       if (loadTimeData.getBoolean('managedUsersEnabled') &&
           loadTimeData.getBoolean('profileIsManaged')) {
         $('managed-user-settings-section').hidden = false;