TestApi for UserSystemPackageInstaller

Introduces a TestApi that lists which system packages
will be pre-installed for the given user type, for
use with CTS tests that need to predict which packages
are installed on a new user.

Test: atest com.android.cts.devicepolicy.DeviceOwnerTest#testCreateAndManageUser_LeaveAllSystemApps
Bug: 189873486
Change-Id: I471c5da55f8cf500a07de5773050a997ea391892

2 files changed, 30 insertions, 0 deletions

diff --git a/core/java/android/os/IUserManager.aidl b/core/java/android/os/IUserManager.aidl
index 9a8194240f8e..3bee4b73dc22 100644
--- a/core/java/android/os/IUserManager.aidl
+++ b/core/java/android/os/IUserManager.aidl
@@ -46,6 +46,7 @@ interface IUserManager {
     UserInfo createProfileForUserWithThrow(in String name, in String userType, int flags, int userId,
             in String[] disallowedPackages);
     UserInfo createRestrictedProfileWithThrow(String name, int parentUserHandle);
+    String[] getPreInstallableSystemPackages(in String userType);
     void setUserEnabled(int userId);
     void setUserAdmin(int userId);
     void evictCredentialEncryptionKey(int userId);
diff --git a/core/java/android/os/UserManager.java b/core/java/android/os/UserManager.java
index 224cd84bc777..59b6ae278e40 100644
--- a/core/java/android/os/UserManager.java
+++ b/core/java/android/os/UserManager.java
@@ -26,6 +26,7 @@ import android.annotation.Nullable;
 import android.annotation.RequiresPermission;
 import android.annotation.StringDef;
 import android.annotation.SuppressAutoDoc;
+import android.annotation.SuppressLint;
 import android.annotation.SystemApi;
 import android.annotation.SystemService;
 import android.annotation.TestApi;
@@ -53,6 +54,7 @@ import android.location.LocationManager;
 import android.provider.Settings;
 import android.telephony.TelephonyManager;
 import android.util.AndroidException;
+import android.util.ArraySet;
 import android.view.WindowManager.LayoutParams;
 
 import com.android.internal.R;
@@ -3200,6 +3202,33 @@ public class UserManager {
     }
 
     /**
+     * Returns the list of the system packages that would be installed on this type of user upon
+     * its creation.
+     *
+     * Returns {@code null} if all system packages would be installed.
+     *
+     * @hide
+     */
+    @TestApi
+    @SuppressLint("NullableCollection")
+    @RequiresPermission(anyOf = {
+            android.Manifest.permission.MANAGE_USERS,
+            android.Manifest.permission.CREATE_USERS
+    })
+    public @Nullable Set<String> getPreInstallableSystemPackages(@NonNull String userType) {
+        try {
+            final String[] installableSystemPackages
+                    = mService.getPreInstallableSystemPackages(userType);
+            if (installableSystemPackages == null) {
+                return null;
+            }
+            return new ArraySet<>(installableSystemPackages);
+        } catch (RemoteException re) {
+            throw re.rethrowFromSystemServer();
+        }
+    }
+
+    /**
      * @hide
      *
      * Returns the preferred account name for user creation.