Fixed {overlay|focus|scrolling} handling on the help page.

BUG=305736
TEST=manual tests on Linux ChromeOS build.

Review URL: https://codereview.chromium.org/50853002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232414 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 27 insertions, 0 deletions

diff --git a/chrome/browser/resources/help/help_focus_manager.js b/chrome/browser/resources/help/help_focus_manager.js
new file mode 100644
index 0000000..335f8fd
--- /dev/null
+++ b/chrome/browser/resources/help/help_focus_manager.js
@@ -0,0 +1,27 @@
+// Copyright 2013 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.
+
+// Helper class for help page, that controls focus transition between
+// elements on the help page and overlays.
+cr.define('help', function() {
+  function HelpFocusManager() {
+  }
+
+  cr.addSingletonGetter(HelpFocusManager);
+
+  HelpFocusManager.prototype = {
+    __proto__: cr.ui.FocusManager.prototype,
+
+    getFocusParent: function() {
+      var page = help.HelpPage.getTopmostVisiblePage();
+      if (!page)
+        return null;
+      return page.pageDiv;
+    },
+  };
+
+  return {
+    HelpFocusManager: HelpFocusManager,
+  };
+});