first-run: Refactor Upgrade class into a common upgrade_util API.

chrome/browser/first_run/upgrade_util.cc

+// Copyright (c) 2011 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/first_run/upgrade_util.h"
+
+#include "base/command_line.h"
+#include "base/logging.h"
+
+namespace {
+
+CommandLine* command_line;
+
+}  // namespace
+
+namespace upgrade_util {
+
+void SetNewCommandLine(CommandLine* new_command_line) {
+  command_line = new_command_line;
+}
+
+void RelaunchChromeBrowserWithNewCommandLineIfNeeded() {
+  if (command_line) {
+    if (!RelaunchChromeBrowser(*command_line)) {
+      DLOG(ERROR) << "Launching a new instance of the browser failed.";
+    } else {
+      DLOG(WARNING) << "Launched a new instance of the browser.";
+    }
+    delete command_line;
+    command_line = NULL;
+  }
+}
+
+}  // namespace upgrade_util