Use PageManager in About page

chrome/browser/ui/webui/options/chromeos/help_overlay_handler.cc

+// Copyright 2014 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 "chrome/browser/ui/webui/options/chromeos/help_overlay_handler.h"
+
+#include "base/basictypes.h"
+#include "base/values.h"
+#include "chrome/browser/ui/webui/help/help_handler.h"
+#include "chrome/common/chrome_switches.h"
+#include "content/public/browser/web_ui.h"
+
+namespace chromeos {
+namespace options {
+
+HelpOverlayHandler::HelpOverlayHandler() {
+}
+
+HelpOverlayHandler::~HelpOverlayHandler() {
+}
+
+void HelpOverlayHandler::GetLocalizedValues(
+    base::DictionaryValue* localized_strings) {
+  HelpHandler::GetLocalizedValues(localized_strings);
+}
+
+void HelpOverlayHandler::RegisterMessages() {
+  if (!::switches::SettingsWindowEnabled())

[Dan Beam, 2014/08/06 18:30:54]

why are we getting here without SettingWindowEnabled() returning true?

[michaelpg, 2014/08/06 21:58:18]

This will be the next CL, but to answer your question, including the help
overlay page in settings means we have to register the localized values, so this
handler has to be added. It would be nice if we could conditionally include the
help overlay HTML so we wouldn't have to localize (or include) a page when we
won't show it -- is that possible?

+    return;
+  HelpHandler* help_handler = new HelpHandler();
+  web_ui()->AddMessageHandler(help_handler);

[Dan Beam, 2014/08/06 18:30:54]

if (::switches::SettingsWindowEnabled())
  web_ui()->AddMessageHandler(new HelpHandler());

+}
+
+}  // namespace options
+}  // namespace chromeos