MD Settings: add a semi-functional System page

chrome/browser/ui/webui/settings/system_handler.cc

+// Copyright 2016 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/settings/system_handler.h"
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/metrics/user_metrics.h"
+#include "base/metrics/user_metrics_action.h"
+#include "content/public/browser/web_ui.h"
+
+namespace settings {
+
+SystemHandler::SystemHandler() {}
+
+SystemHandler::~SystemHandler() {}
+
+void SystemHandler::RegisterMessages() {
+  web_ui()->RegisterMessageCallback("changeProxySettings",
+      base::Bind(&SystemHandler::HandleChangeProxySettings,
+                 base::Unretained(this)));
+}
+
+void SystemHandler::HandleChangeProxySettings(const base::ListValue* /*args*/) {
+  base::RecordAction(base::UserMetricsAction("Options_ShowProxySettings"));
+  // TODO(dbeam): port AdvancedOptionsUtilities::ShowNetworkProxySettings from
+  // advanced_options_utils.h to new, settings accessible place.
+}
+
+}  // namespace settings