DevicePolicyManager Authentication for Lock Task

Here we let DevicePolicyManager keep a list of tasks that are
allowed to start the lock task mode. This list can only be set by
a device owner app. The ActivityManager will call
DevicePolicyManager to check whether a given task can start the
lock task mode or not.

Change-Id: I650fdae43fc35bf9fd63452283f4e2bbadd11551
Bug: 14611303
4 files changed