Moved JsonPrefStore to use SequencedWorkerPool

chrome/browser/chrome_browser_main.cc

Index: chrome/browser/chrome_browser_main.cc
diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index 309041ee9d42ee2629b730926910227b5fc03633..67ce788d5401e08f9a1d21b7fcbed996441f6f79 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -25,6 +25,7 @@
 #include "base/string_split.h"
 #include "base/sys_string_conversions.h"
 #include "base/threading/platform_thread.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
@@ -310,6 +311,13 @@ PrefService* InitializeLocalState(const CommandLine& parsed_command_line,
 #endif  // defined(OS_WIN)
   }
 
+  scoped_refptr<base::SequencedTaskRunner> sequenced_task_runner =
+      BrowserThread::GetBlockingPool()->
+        GetSequencedTaskRunnerWithShutdownBehavior(
+            BrowserThread::GetBlockingPool()->GetNamedSequenceToken(
+                "local_state_pool"),
+            base::SequencedWorkerPool::BLOCK_SHUTDOWN);
+
   // If the local state file for the current profile doesn't exist and the
   // parent profile command line flag is present, then we should inherit some
   // local state from the parent profile.
@@ -325,7 +333,7 @@ PrefService* InitializeLocalState(const CommandLine& parsed_command_line,
     scoped_ptr<PrefService> parent_local_state(
         PrefService::CreatePrefService(parent_profile,
                                        g_browser_process->policy_service(),
-                                       NULL, false));
+                                       NULL, false, sequenced_task_runner));
     parent_local_state->RegisterStringPref(prefs::kApplicationLocale,
                                            std::string());
     // Right now, we only inherit the locale setting from the parent profile.