Code quality and standards in SimpleBackend.

net/disk_cache/simple/simple_synchronous_entry.h

 // Copyright (c) 2013 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 NET_DISK_CACHE_SIMPLE_SIMPLE_SYNCHRONOUS_ENTRY_H_
 #define NET_DISK_CACHE_SIMPLE_SIMPLE_SYNCHRONOUS_ENTRY_H_
 
 #include <string>
 
 #include "base/callback_forward.h"
@@ skipping 27 matching lines @@
   typedef base::Callback<void(SimpleSynchronousEntry* new_entry)>
       SynchronousCreationCallback;
 
   // Callback type for IO operations on an entry not requiring special callback
   // arguments (e.g. Write). |result| is a net::Error result code.
   typedef base::Callback<void(int result)> SynchronousOperationCallback;
 
   static void OpenEntry(
       const base::FilePath& path,
       const std::string& key,
-      const scoped_refptr<base::TaskRunner>& callback_runner,
+      base::SingleThreadTaskRunner* callback_runner,
       const SynchronousCreationCallback& callback);
 
   static void CreateEntry(
       const base::FilePath& path,
       const std::string& key,
-      const scoped_refptr<base::TaskRunner>& callback_runner,
+      base::SingleThreadTaskRunner* callback_runner,
       const SynchronousCreationCallback& callback);
 
   // Deletes an entry without first Opening it. Does not check if there is
   // already an Entry object in memory holding the open files. Be careful! This
   // is meant to be used by the Backend::DoomEntry() call. |callback| will be
   // run by |callback_runner|.
   static void DoomEntry(const base::FilePath& path,
                         const std::string& key,
-                        const scoped_refptr<base::TaskRunner>& callback_runner,
+                        base::SingleThreadTaskRunner* callback_runner,
                         const net::CompletionCallback& callback);
 
   // N.B. Close(), ReadData() and WriteData() may block on IO.
   void Close();
   void ReadData(int index,
                 int offset,
                 net::IOBuffer* buf,
                 int buf_len,
                 const SynchronousOperationCallback& callback);
   void WriteData(int index,
                  int offset,
                  net::IOBuffer* buf,
                  int buf_len,
                  const SynchronousOperationCallback& callback,
                  bool truncate);
 
   const base::FilePath& path() const { return path_; }
   std::string key() const { return key_; }
   base::Time last_used() const { return last_used_; }
   base::Time last_modified() const { return last_modified_; }
   int32 data_size(int index) const { return data_size_[index]; }
 
   int64 GetFileSize() const;
 
  private:
   SimpleSynchronousEntry(
-      const scoped_refptr<base::TaskRunner>& callback_runner,
+      base::SingleThreadTaskRunner* callback_runner,
       const base::FilePath& path,
       const std::string& key);
 
   // Like Entry, the SimpleSynchronousEntry self releases when Close() is
   // called.
   ~SimpleSynchronousEntry();
 
   bool OpenOrCreateFiles(bool create);
 
   // Returns a net::Error, i.e. net::OK on success.
   int InitializeForOpen();
 
   // Returns a net::Error, including net::OK on success and net::FILE_EXISTS
   // when the entry already exists.
   int InitializeForCreate();
 
   void Doom();
 
-  scoped_refptr<base::TaskRunner> callback_runner_;
+  scoped_refptr<base::SingleThreadTaskRunner> callback_runner_;
   const base::FilePath path_;
   const std::string key_;
 
   bool initialized_;
 
   base::Time last_used_;
   base::Time last_modified_;
   int32 data_size_[kSimpleEntryFileCount];
 
   base::PlatformFile files_[kSimpleEntryFileCount];
 };
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_SIMPLE_SIMPLE_SYNCHRONOUS_ENTRY_H_