Note DPM.wipeData() on a secondary user is now blocking, just like
it's been always blocking on the primary user.
Test: Manually tested wipeData() with TestDPC, both on 1) the primary user,
2) a secondary user and 3) work profile.
* Modified TestDPC so it supports secondary users
Test: adb shell am instrument -e class com.android.server.devicepolicy.DevicePolicyManagerTest -w com.android.frameworks.servicestests
Bug 30681079
Change-Id: Ib97a92a6af87a5589d2643b9ae0522395735e1a5
a755fb1030