Add new permission for am.updateLockTaskPackages()

Adds android.permission.UPDATE_LOCK_TASK_PACKAGES, available only to
the system and setup wizard, providing access to
updateLockTaskPackages() without registering with the device policy
manager as a device owner.

Bug: 20016740
Change-Id: I6eceb5cece9407c84eabf3a818bb908f95989b91
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 8abb7e2..10084c8 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -2975,6 +2975,11 @@
     <permission android:name="android.permission.BIND_VR_LISTENER_SERVICE"
         android:protectionLevel="signature" />
 
+    <!-- Allows an application to whitelist tasks during lock task mode
+         @hide <p>Not for use by third-party applications.</p> -->
+    <permission android:name="android.permission.UPDATE_LOCK_TASK_PACKAGES"
+        android:protectionLevel="signature|setup" />
+
     <application android:process="system"
                  android:persistent="true"
                  android:hasCode="false"
diff --git a/services/core/java/com/android/server/am/ActivityManagerService.java b/services/core/java/com/android/server/am/ActivityManagerService.java
index 4bb3a54..1fe2622 100644
--- a/services/core/java/com/android/server/am/ActivityManagerService.java
+++ b/services/core/java/com/android/server/am/ActivityManagerService.java
@@ -9823,7 +9823,8 @@
     public void updateLockTaskPackages(int userId, String[] packages) {
         final int callingUid = Binder.getCallingUid();
         if (callingUid != 0 && callingUid != Process.SYSTEM_UID) {
-            throw new SecurityException("updateLockTaskPackage called from non-system process");
+            enforceCallingPermission(android.Manifest.permission.UPDATE_LOCK_TASK_PACKAGES,
+                    "updateLockTaskPackages()");
         }
         synchronized (this) {
             if (DEBUG_LOCKTASK) Slog.w(TAG_LOCKTASK, "Whitelisting " + userId + ":" +