tree 4ca17c403f8756207d6b931fd2d4c1a8309bec6e
parent ea868b3846794cd36424f477503377ea9348137a
author Doug Zongker <dougz@android.com> 1378327478 -0700
committer Doug Zongker <dougz@google.com> 1394572788 -0700

allow CheckKey to request mounting /system

Also provide a default implementation of CheckKey that's reasonable
for many devices (those that have power and volume keys).

Change-Id: Icf6c7746ebd866152d402059dbd27fd16bd51ff8