Implement sideload wipeout for Extensions.

chrome/browser/resources/extensions/extensions.js

 // 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.
 
 <include src="../uber/uber_utils.js"></include>
 <include src="extension_commands_overlay.js"></include>
 <include src="extension_focus_manager.js"></include>
 <include src="extension_list.js"></include>
 <include src="pack_extension_overlay.js"></include>
 
@@ skipping 234 matching lines @@
     if (extensionsData.managedMode) {
       pageDiv.classList.add('showing-banner');
       pageDiv.classList.add('managed-mode');
       $('toggle-dev-on').disabled = true;
     } else {
       pageDiv.classList.remove('showing-banner');
       pageDiv.classList.remove('managed-mode');
       $('toggle-dev-on').disabled = false;
     }
 
+    if (extensionsData.showDisabledExtensionsWarning) {
+      pageDiv.classList.add('showing-banner');
+      pageDiv.classList.add('sideload-wipeout');
+
+      // If we have two banners showing, make sure to have the room for both.
+      if (pageDiv.classList.contains('managed-mode'))
+        pageDiv.style.marginTop = '105px';
+    }
+
     if (extensionsData.developerMode && !extensionsData.managedMode) {
       pageDiv.classList.add('dev-mode');
       $('toggle-dev-on').checked = true;
       $('dev-controls').hidden = false;
     } else {
       pageDiv.classList.remove('dev-mode');
       $('toggle-dev-on').checked = false;
     }
 
     $('load-unpacked').disabled = extensionsData.loadUnpackedDisabled;
@@ skipping 85 matching lines @@
   return {
     ExtensionSettings: ExtensionSettings
   };
 });
 
 var ExtensionSettings = extensions.ExtensionSettings;
 
 window.addEventListener('load', function(e) {
   ExtensionSettings.getInstance().initialize();
 });