Reinitialize LocalState's CommandLinePrefStore after about_flags updates the command line.

chrome/browser/prefs/pref_value_store.h

Index: chrome/browser/prefs/pref_value_store.h
===================================================================
--- chrome/browser/prefs/pref_value_store.h	(revision 118876)
+++ chrome/browser/prefs/pref_value_store.h	(working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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.
 
@@ -105,6 +105,9 @@
   // whether there is no higher-priority source controlling it.
   bool PrefValueExtensionModifiable(const char* name) const;
 
+  // Update the command line PrefStore with |command_line_prefs|.
+  void UpdateCommandLinePrefStore(PrefStore* command_line_prefs);
+
  private:
   // PrefStores must be listed here in order from highest to lowest priority.
   //   MANAGED_PLATFORM contains all managed preference values that are