This wrapper will be part of usb emulation backend.
BUG=chromium:831850
TEST=local build
Change-Id: I084b15201941e4c16c4e3ff9b967e55db09db567
Reviewed-on: https://chromium-review.googlesource.com/1124870
Commit-Ready: Jingkui Wang <jkwang@google.com>
Tested-by: Jingkui Wang <jkwang@google.com>
Reviewed-by: Jingkui Wang <jkwang@google.com>