Disable modifying extensions when in managed mode.

chrome/browser/resources/options2/chromeos/internet_detail.html

Index: chrome/browser/resources/options2/chromeos/internet_detail.html
===================================================================
--- chrome/browser/resources/options2/chromeos/internet_detail.html	(revision 141651)
+++ chrome/browser/resources/options2/chromeos/internet_detail.html	(working copy)
@@ -453,8 +453,8 @@
     <div id="network-proxy-tab" class="subpages-tab-contents">
       <section>
         <div id="info-banner" hidden>
-          <span id="banner-icon" class="managed-prefs-icon"></span>
-          <span id="banner-text" class="managed-prefs-text"></span>
+          <span id="banner-icon" class="main-page-banner-icon"></span>
+          <span id="banner-text" class="main-page-banner-text"></span>

[Patrick Dubroy, 2012/06/18 12:13:01]

IMO the old name was more descriptive.

[Pam (message me for reviews), 2012/06/18 18:26:00]

Yep. But it's using shared CSS now, so it needs a more general shared name.

[Patrick Dubroy, 2012/06/19 13:01:52]

IMO "main-page-banner" is still not the best name. Is it the banner of the main
page, or the main banner of the page? I think I'd just call it a page banner.

[Pam (message me for reviews), 2012/06/19 20:37:46]

Fair enough.

         </div>
         <div class="radio">
           <label>