Device Owner, a special kind of device admin

A Device Owner cannot be uninstalled and is available to all users. It must
be registered before the device_provisioned flag is set.

Device admins can be disabled until used, but visible to device policy
manager, so that users wont be bothered with update requests.

Opened up a few related APIs for use by a system-installed Device Owner.

Change-Id: I847b5fe68c0f724863f778a67602b5bddc79d8e5
diff --git a/core/java/android/app/admin/IDevicePolicyManager.aidl b/core/java/android/app/admin/IDevicePolicyManager.aidl
index e061ab3..b2a65bf 100644
--- a/core/java/android/app/admin/IDevicePolicyManager.aidl
+++ b/core/java/android/app/admin/IDevicePolicyManager.aidl
@@ -97,4 +97,8 @@
         int numbers, int symbols, int nonletter, int userHandle);
     void reportFailedPasswordAttempt(int userHandle);
     void reportSuccessfulPasswordAttempt(int userHandle);
+
+    boolean setDeviceOwner(String packageName);
+    boolean isDeviceOwner(String packageName);
+    String getDeviceOwner();
 }