The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1110cd1a1affaaf2b956103ee7fd1b76fc926b11

commit 1110cd1a1affaaf2b956103ee7fd1b76fc926b11
Author: hashimoto <hashimoto@chromium.org>
Date: Wed Dec 14 09:42:46 2016

arc: Implement ArcContentFileSystemFileStreamReader offset handling

Replace net::FileStream with base::File for finer errno handling.

BUG= 671510 
TEST=unit_tests

Review-Url: https://codereview.chromium.org/2551913004
Cr-Commit-Position: refs/heads/master@{#438473}

[modify] https://crrev.com/1110cd1a1affaaf2b956103ee7fd1b76fc926b11/chrome/browser/chromeos/arc/fileapi/arc_content_file_system_file_stream_reader.cc
[modify] https://crrev.com/1110cd1a1affaaf2b956103ee7fd1b76fc926b11/chrome/browser/chromeos/arc/fileapi/arc_content_file_system_file_stream_reader.h
[modify] https://crrev.com/1110cd1a1affaaf2b956103ee7fd1b76fc926b11/chrome/browser/chromeos/arc/fileapi/arc_content_file_system_file_stream_reader_unittest.cc