Note that we also don't need to use io_buffer directly anymore now that HID is behind a mojo service. Removing io_buffer may reduce the work you need to do to re-land these CLs.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/571fe62bc1973e99971da3c211b34042c3c7831d

commit 571fe62bc1973e99971da3c211b34042c3c7831d
Author: Jun Choi <hongjunchoi@chromium.org>
Date: Tue Nov 14 00:27:55 2017

Reland "Update U2fPacket::GetSerializedData() to get rid of report_id."

Fixed bug introduced from r513104 by removing report ID from
serialization buffer both when reading from and writing to hid
devices. Also,removed use of net::IOBuffer since U2f Hid devices are
now servicified.

Bug:  782825 
Change-Id: I084337af2e2355a74f2a888b5164ecb9c16cc9a0
Reviewed-on: https://chromium-review.googlesource.com/765058
Commit-Queue: Jun Choi <hongjunchoi@chromium.org>
Reviewed-by: Reilly Grant <reillyg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516117}
[modify] https://crrev.com/571fe62bc1973e99971da3c211b34042c3c7831d/device/u2f/u2f_hid_device.cc
[modify] https://crrev.com/571fe62bc1973e99971da3c211b34042c3c7831d/device/u2f/u2f_message.cc
[modify] https://crrev.com/571fe62bc1973e99971da3c211b34042c3c7831d/device/u2f/u2f_message.h
[modify] https://crrev.com/571fe62bc1973e99971da3c211b34042c3c7831d/device/u2f/u2f_message_unittest.cc
[modify] https://crrev.com/571fe62bc1973e99971da3c211b34042c3c7831d/device/u2f/u2f_packet.cc
[modify] https://crrev.com/571fe62bc1973e99971da3c211b34042c3c7831d/device/u2f/u2f_packet.h