Hook up the SequencedWorkerPool to the browser thread.

chrome/browser/visitedlink/visitedlink_master.h

 // 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.
 
 #ifndef CHROME_BROWSER_VISITEDLINK_VISITEDLINK_MASTER_H_
 #define CHROME_BROWSER_VISITEDLINK_VISITEDLINK_MASTER_H_
 #pragma once
 
 #if defined(OS_WIN)
 #include <windows.h>
 #endif
 #include <set>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/file_path.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/shared_memory.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "chrome/browser/history/history.h"
 #include "chrome/common/visitedlink_common.h"
 
 class GURL;
 class Profile;
 
 // Controls the link coloring database. The master controls all writing to the
 // database as well as disk I/O. There should be only one master.
 //
 // This class will defer writing operations to the file thread. This means that
@@ skipping 126 matching lines @@
   void InitMembers(Listener* listener, Profile* profile);
 
   // If a rebuild is in progress, we save the URL in the temporary list.
   // Otherwise, we add this to the table. Returns the index of the
   // inserted fingerprint or null_hash_ on failure.
   Hash TryToAddURL(const GURL& url);
 
   // File I/O functions
   // ------------------
 
+  // Posts the given task to the blocking worker pool with our options.
+  void PostIOTask(const tracked_objects::Location& from_here,
+                  const base::Closure& task);
+
   // Writes the entire table to disk, returning true on success. It will leave
   // the table file open and the handle to it in file_
   bool WriteFullTable();
 
   // Try to load the table from the database file. If the file doesn't exist or
   // is corrupt, this will return failure.
   bool InitFromFile();
 
   // Reads the header of the link coloring database from disk. Assumes the
   // file pointer is at the beginning of the file and that there are no pending
@@ skipping 129 matching lines @@
   // are pending, yet we don't track whether they have been completed. This
   // flag is a sanity check that these reads only happen before any
   // asynchronous writes have been fired.
   bool posted_asynchronous_operation_;
 #endif
 
   // Reference to the user profile that this object belongs to
   // (it knows the path to where the data is stored)
   Profile* profile_;
 
+  // Lazily initialized sequence token for posting file tasks.
+  base::SequencedWorkerPool::SequenceToken sequence_token_;
+
   // When non-NULL, indicates we are in database rebuild mode and points to
   // the class collecting fingerprint information from the history system.
   // The pointer is owned by this class, but it must remain valid while the
   // history query is running. We must only delete it when the query is done.
   scoped_refptr<TableBuilder> table_builder_;
 
   // Indicates URLs added and deleted since we started rebuilding the table.
   std::set<Fingerprint> added_since_rebuild_;
   std::set<Fingerprint> deleted_since_rebuild_;
 
@@ skipping 55 matching lines @@
   int32 used_count = 0;
   for (int32 i = 0; i < table_length_; i++) {
     if (hash_table_[i])
       used_count++;
   }
   DCHECK_EQ(used_count, used_items_);
 }
 #endif
 
 #endif  // CHROME_BROWSER_VISITEDLINK_VISITEDLINK_MASTER_H_