Add Transient FileSystem which goes away after its snapsot file is gone

webkit/fileapi/webkit_fileapi.gypi

 # Copyright (c) 2012 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.
 
 {
   'variables': {
     'webkit_fileapi_sources': [
       '../fileapi/async_file_util.h',
       '../fileapi/async_file_util_adapter.cc',
       '../fileapi/async_file_util_adapter.h',
@@ skipping 93 matching lines @@
       '../fileapi/syncable/sync_status_code.h',
       '../fileapi/syncable/syncable_file_operation_runner.cc',
       '../fileapi/syncable/syncable_file_operation_runner.h',
       '../fileapi/syncable/syncable_file_system_operation.cc',
       '../fileapi/syncable/syncable_file_system_operation.h',
       '../fileapi/syncable/syncable_file_system_util.cc',
       '../fileapi/syncable/syncable_file_system_util.h',
       '../fileapi/task_runner_bound_observer_list.h',
       '../fileapi/test_mount_point_provider.cc',
       '../fileapi/test_mount_point_provider.h',
+      '../fileapi/transient_file_util.cc',
+      '../fileapi/transient_file_util.h',
       '../fileapi/upload_file_system_file_element_reader.cc',
       '../fileapi/upload_file_system_file_element_reader.h',
       '../fileapi/webfilewriter_base.cc',
       '../fileapi/webfilewriter_base.h',
     ],
     'webkit_fileapi_chromeos_sources': [
       '../chromeos/fileapi/async_file_stream.h',
       '../chromeos/fileapi/cros_mount_point_provider.cc',
       '../chromeos/fileapi/cros_mount_point_provider.h',
       '../chromeos/fileapi/file_access_permissions.cc',
@@ skipping 12 matching lines @@
       'sources': [
         '../fileapi/dump_file_system.cc',
       ],
       'dependencies': [
         '../../base/base.gyp:base',
         '../support/webkit_support.gyp:webkit_storage',
       ],
     },
   ],
 }