Use ArcFileSystemInstance to access files on ARC.

chrome/browser/chromeos/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//extensions/features/features.gni")
 import("//media/media_options.gni")
 import("//printing/features/features.gni")
 import("//third_party/protobuf/proto_library.gni")
@@ skipping 212 matching lines @@
     "arc/fileapi/arc_content_file_system_async_file_util.cc",
     "arc/fileapi/arc_content_file_system_async_file_util.h",
     "arc/fileapi/arc_content_file_system_backend_delegate.cc",
     "arc/fileapi/arc_content_file_system_backend_delegate.h",
     "arc/fileapi/arc_content_file_system_file_stream_reader.cc",
     "arc/fileapi/arc_content_file_system_file_stream_reader.h",
     "arc/fileapi/arc_content_file_system_service.cc",
     "arc/fileapi/arc_content_file_system_service.h",
     "arc/fileapi/arc_content_file_system_url_util.cc",
     "arc/fileapi/arc_content_file_system_url_util.h",
-    "arc/fileapi/intent_helper_util.cc",
-    "arc/fileapi/intent_helper_util.h",
+    "arc/fileapi/arc_file_system_util.cc",

[hashimoto, 2016/11/18 08:00:12]

suggestion: "file system util" sounds a bit ambiguous (anything under
arc/fileapi should be related to file systems after all). How about something
more specific? (e.g. arc_file_system_instance_util.cc)

[Shuhei Takahashi, 2016/11/18 08:41:03]

Sounds good, done.

+    "arc/fileapi/arc_file_system_util.h",
     "arc/intent_helper/arc_external_protocol_dialog.cc",
     "arc/intent_helper/arc_external_protocol_dialog.h",
     "arc/intent_helper/arc_navigation_throttle.cc",
     "arc/intent_helper/arc_navigation_throttle.h",
     "arc/intent_helper/arc_settings_service.cc",
     "arc/intent_helper/arc_settings_service.h",
     "arc/notification/arc_boot_error_notification.cc",
     "arc/notification/arc_boot_error_notification.h",
     "arc/optin/arc_optin_preference_handler.cc",
     "arc/optin/arc_optin_preference_handler.h",
@@ skipping 1400 matching lines @@
     "policy/proto/chrome_device_policy.proto",
     "policy/proto/install_attributes.proto",
   ]
 }
 
 proto_library("attestation_proto") {
   sources = [
     "attestation/attestation_key_payload.proto",
   ]
 }