Moved JsonPrefStore to use SequencedWorkerPool

chrome/browser/automation/testing_automation_provider.cc

Index: chrome/browser/automation/testing_automation_provider.cc
diff --git a/chrome/browser/automation/testing_automation_provider.cc b/chrome/browser/automation/testing_automation_provider.cc
index 47a4a1220f4dff350722d8a8af2b44a302298706..8479e641c224bb809b573536d5a8aaa2010be9b3 100644
--- a/chrome/browser/automation/testing_automation_provider.cc
+++ b/chrome/browser/automation/testing_automation_provider.cc
@@ -19,6 +19,7 @@
 #include "base/path_service.h"
 #include "base/process.h"
 #include "base/process_util.h"
+#include "base/sequenced_task_runner.h"
 #include "base/stringprintf.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time.h"
@@ -1288,7 +1289,9 @@ void TestingAutomationProvider::GetBookmarksAsJSON(
     return;
   }
   scoped_refptr<BookmarkStorage> storage(
-      new BookmarkStorage(browser->profile(), bookmark_model));
+      new BookmarkStorage(browser->profile(),
+                          bookmark_model,
+                          browser->profile()->GetIOTaskRunner()));
   if (!storage->SerializeData(&bookmarks_as_json)) {
     reply.SendError("Failed to serialize bookmarks");
     return;