Revert 60378 (trying to track down http://crbug.com/56752 )- Flesh out URLLoa...

webkit/blob/deletable_file_reference.cc

-// Copyright (c) 2010 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.
-
-#include "webkit/blob/deletable_file_reference.h"
-
-#include <map>
-#include "base/file_util.h"
-#include "base/file_util_proxy.h"
-#include "base/message_loop_proxy.h"
-#include "base/singleton.h"
-
-namespace webkit_blob {
-
-namespace {
-
-typedef std::map<FilePath, DeletableFileReference*> DeleteableFileMap;
-
-DeleteableFileMap* map() {
-  return Singleton<DeleteableFileMap>::get();
-}
-
-}  // namespace
-
-// static
-scoped_refptr<DeletableFileReference> DeletableFileReference::Get(
-    const FilePath& path) {
-  DeleteableFileMap::iterator found = map()->find(path);
-  DeletableFileReference* reference =
-      (found == map()->end()) ? NULL : found->second;
-  return scoped_refptr<DeletableFileReference>(reference);
-}
-
-// static
-scoped_refptr<DeletableFileReference> DeletableFileReference::GetOrCreate(
-    const FilePath& path, base::MessageLoopProxy* file_thread) {
-  DCHECK(file_thread);
-  typedef std::pair<DeleteableFileMap::iterator, bool> InsertResult;
-  InsertResult result = map()->insert(
-      DeleteableFileMap::value_type(path, NULL));
-  if (result.second == false)
-    return scoped_refptr<DeletableFileReference>(result.first->second);
-
-  // Wasn't in the map, create a new reference and store the pointer.
-  scoped_refptr<DeletableFileReference> reference =
-      new DeletableFileReference(path, file_thread);
-  result.first->second = reference.get();
-  return reference;
-}
-
-DeletableFileReference::DeletableFileReference(
-    const FilePath& path, base::MessageLoopProxy* file_thread)
-    : path_(path), file_thread_(file_thread) {
-  DCHECK(map()->find(path_)->second == NULL);
-}
-
-DeletableFileReference::~DeletableFileReference() {
-  DCHECK(map()->find(path_)->second == this);
-  map()->erase(path_);
-  base::FileUtilProxy::Delete(file_thread_, path_, NULL);
-}
-
-}  // namespace webkit_blob