[iOS] Support for chrome://version

ios/chrome/browser/ui/webui/version_handler.cc

+// Copyright 2015 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 "ios/chrome/browser/ui/webui/version_handler.h"
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/values.h"
+#include "components/version_ui/version_handler_helper.h"
+#include "components/version_ui/version_ui_constants.h"
+#include "ios/public/provider/web/web_ui_ios.h"
+#include "ui/base/l10n/l10n_util.h"
+
+VersionHandler::VersionHandler() {}
+
+VersionHandler::~VersionHandler() {}
+
+void VersionHandler::RegisterMessages() {
+  web_ui()->RegisterMessageCallback(
+      version_ui::kRequestVersionInfo,
+      base::Bind(&VersionHandler::HandleRequestVersionInfo,
+                 base::Unretained(this)));
+}
+
+void VersionHandler::HandleRequestVersionInfo(const base::ListValue* args) {
+  // Respond with the variations info immediately.
+  web_ui()->CallJavascriptFunction(version_ui::kReturnVariationInfo,
+                                   *version_ui::GetVariationsList());
+}