Add a lock to the managed user settings page and require authentication for unlocking.

chrome/browser/resources/options/managed_user_set_passphrase.js

Index: chrome/browser/resources/options/managed_user_set_passphrase.js
diff --git a/chrome/browser/resources/options/managed_user_set_passphrase.js b/chrome/browser/resources/options/managed_user_set_passphrase.js
new file mode 100644
index 0000000000000000000000000000000000000000..e2b1c6ede51bb410e01b0481f7337e4fffa02c41
--- /dev/null
+++ b/chrome/browser/resources/options/managed_user_set_passphrase.js
@@ -0,0 +1,68 @@
+// 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.
+
+cr.define('options', function() {
+  /** @const */ var OptionsPage = options.OptionsPage;
+
+  //////////////////////////////////////////////////////////////////////////////
+  // ManagedUserSetPassphraseOverlay class:
+
+  /**
+   * Encapsulated handling of the Managed User Set Passphrase page.
+   * @constructor
+   */
+  function ManagedUserSetPassphraseOverlay() {
+    OptionsPage.call(
+      this,
+      'setPassphrase',
+      loadTimeData.getString('setPassphraseTitle'),
+      'managed-user-set-passphrase-overlay');
+  }
+
+  cr.addSingletonGetter(ManagedUserSetPassphraseOverlay);
+
+  ManagedUserSetPassphraseOverlay.prototype = {
+    __proto__: OptionsPage.prototype,
+
+    /** @override */
+    initializePage: function() {
+      OptionsPage.prototype.initializePage.call(this);
+      $('passphrase').oninput = this.updateDisplay_;
+      $('passphrase-confirm').oninput = this.updateDisplay_;
+
+      $('save-passphrase').onclick = function() {
+        if ($('passphrase').value != $('passphrase-confirm').value) {
+          $('passphrase-mismatch').hidden = false;
+          return;
+        }
+        chrome.send('setPassphrase', [$('passphrase').value]);
+        $('passphrase').value = '';
+        $('passphrase-confirm').value = '';
+        OptionsPage.closeOverlay();
+      };
+    },
+    updateDisplay_: function() {
+      if ($('passphrase-confirm').value != $('passphrase').value) {
+        $('passphrase-mismatch').hidden = false;
+        $('passphrase-confirm').classList.add('unequal-passphrases');
+        $('save-passphrase').disabled = true;
+      }
+      else {
+        $('save-passphrase').disabled = $('passphrase-confirm').value == '';
+        $('passphrase-mismatch').hidden = true;
+        $('passphrase-confirm').classList.remove('unequal-passphrases');
+      }
+    },
+    didClosePage: function() {
+      chrome.send('endAuthentication');
+      ManagedUserSettings.getInstance().authenticationChecked = false;
+    },
+  };
+
+  // Export
+  return {
+    ManagedUserSetPassphraseOverlay: ManagedUserSetPassphraseOverlay
+  };
+
+});