Allow uninstalling DMRH when not used for management

Bug: 360807442
Test: btest a.d.c.DevicePolicyManagementRoleHolderTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:da522df80568c158fe30896f9a571d05556ee51a)
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:085f90a604ac24e45f44301257ae8a12da0054c1)
Merged-In: I023f78cef11fb7e8e9a92e2896cf94c9fcd1113b
Change-Id: I023f78cef11fb7e8e9a92e2896cf94c9fcd1113b

services/core/java/com/android/server/pm/PackageManagerService.java

@@ -3226,8 +3226,9 @@ public boolean isPackageDeviceAdminOnAnyUser(@NonNull Computer snapshot, String
     // TODO(b/261957226): centralise this logic in DPM
     boolean isPackageDeviceAdmin(String packageName, int userId) {
         final IDevicePolicyManager dpm = getDevicePolicyManager();
+        final UserManagerInternal userManagerInternal = mInjector.getUserManagerInternal();
         try {
-            if (dpm != null) {
+            if (dpm != null && userManagerInternal != null) {
                 final ComponentName deviceOwnerComponentName = dpm.getDeviceOwnerComponent(
                         /* callingUserOnly =*/ false);
                 final String deviceOwnerPackageName = deviceOwnerComponentName == null ? null
@@ -3240,17 +3241,31 @@ boolean isPackageDeviceAdmin(String packageName, int userId) {
                     return true;
                 }
                 // Does it contain a device admin for any user?
-                int[] users;
+                int[] allUsers = mUserManager.getUserIds();
+                int[] targetUsers;
                 if (userId == UserHandle.USER_ALL) {
-                    users = mUserManager.getUserIds();
+                    targetUsers = allUsers;
                 } else {
-                    users = new int[]{userId};
+                    targetUsers = new int[]{userId};
                 }
-                for (int i = 0; i < users.length; ++i) {
-                    if (dpm.packageHasActiveAdmins(packageName, users[i])) {
+
+                for (int i = 0; i < targetUsers.length; ++i) {
+                    if (dpm.packageHasActiveAdmins(packageName, targetUsers[i])) {
                         return true;
                     }
-                    if (isDeviceManagementRoleHolder(packageName, users[i])) {
+                }
+
+                // If a package is DMRH on a managed user, it should also be treated as an admin on
+                // that user. If that package is also a system package, it should also be protected
+                // on other users otherwise "uninstall updates" on an unmanaged user may break
+                // management on other users because apk version is shared between all users.
+                var packageState = snapshotComputer().getPackageStateInternal(packageName);
+                if (packageState == null) {
+                    return false;
+                }
+                for (int user : packageState.isSystem() ? allUsers : targetUsers) {
+                    if (isDeviceManagementRoleHolder(packageName, user)
+                            && userManagerInternal.isUserManaged(user)) {
                         return true;
                     }
                 }