Componentize internal class FlagsState in flags_ui component.

components/flags_ui/flags_ui_switches.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 "components/flags_ui/flags_ui_switches.h"
+
+namespace switches {
+
+// These two flags are added around the switches about:flags adds to the
+// command line. This is useful to see which switches were added by about:flags
+// on about:version. They don't have any effect.
+const char kFlagSwitchesBegin[] = "flag-switches-begin";
+const char kFlagSwitchesEnd[] = "flag-switches-end";
+
+}  // namespace switches