[FileAPI] Replace default leveldb::Env with leveldb::MemEnv in tests.

webkit/browser/fileapi/plugin_private_file_system_backend.cc

 // Copyright 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.
 
 #include "webkit/browser/fileapi/plugin_private_file_system_backend.h"
 
 #include <map>
 
 #include "base/stl_util.h"
 #include "base/synchronization/lock.h"
@@ skipping 80 matching lines @@
     const FileSystemOptions& file_system_options)
     : file_task_runner_(file_task_runner),
       file_system_options_(file_system_options),
       base_path_(profile_path.Append(
           kFileSystemDirectory).Append(kPluginPrivateDirectory)),
       plugin_map_(new FileSystemIDToPluginMap(file_task_runner)),
       weak_factory_(this) {
   file_util_.reset(
       new AsyncFileUtilAdapter(new ObfuscatedFileUtil(
           special_storage_policy,
-          base_path_,
+          base_path_, file_system_options.env_override(),
           file_task_runner,
           base::Bind(&FileSystemIDToPluginMap::GetPluginIDForURL,
                      base::Owned(plugin_map_)),
           std::set<std::string>(),
           NULL)));
 }
 
 PluginPrivateFileSystemBackend::~PluginPrivateFileSystemBackend() {
   if (!file_task_runner_->RunsTasksOnCurrentThread()) {
     AsyncFileUtil* file_util = file_util_.release();
@@ skipping 176 matching lines @@
     FileSystemType type) const {
   return NULL;
 }
 
 ObfuscatedFileUtil* PluginPrivateFileSystemBackend::obfuscated_file_util() {
   return static_cast<ObfuscatedFileUtil*>(
       static_cast<AsyncFileUtilAdapter*>(file_util_.get())->sync_file_util());
 }
 
 }  // namespace fileapi