tree 931fe6f2d5f621cf173a0898587e10ab7653063f
parent 219b708cc94dcc7fdddf9cecd54fcc2005c9fd9e
author Tom Wai-Hong Tam <waihong@chromium.org> 1274939442 +0800
committer David McMahon <djmm@chromium.org> 1275098458 -0700

For USB ethernet device, it failed by directory existed but the two files (device and vendor) not exited. So now check the two files to ensure the present of Ethernet device.

Also fix a bug that not output of lspci/lsusb was considered as device exists.

BUG=3578

Review URL: http://codereview.chromium.org/2279001
(cherry picked from commit 6006f33dc8c9ae955c6ac041d8fe54fb9873aea1)