RESTRICT AUTOMERGE Prevent non-admin users from deleting system apps. am: 7fdc96aef4

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19532979

Change-Id: I57b5bdc0fe501fd27516f3f9ea3c156aa6da6c0f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

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

@@ -18729,6 +18729,17 @@ public class PackageManagerService extends IPackageManager.Stub
                 return PackageManager.DELETE_FAILED_INTERNAL_ERROR;
             }
 
+            if (isSystemApp(uninstalledPs)
+                    && (deleteFlags & PackageManager.DELETE_SYSTEM_APP) == 0) {
+                UserInfo userInfo = sUserManager.getUserInfo(userId);
+                if (userInfo == null || !userInfo.isAdmin()) {
+                    Slog.w(TAG, "Not removing package " + packageName
+                            + " as only admin user may downgrade system apps");
+                    EventLog.writeEvent(0x534e4554, "170646036", -1, packageName);
+                    return PackageManager.DELETE_FAILED_USER_RESTRICTED;
+                }
+            }
+
             disabledSystemPs = mSettings.getDisabledSystemPkgLPr(packageName);
             // Save the enabled state before we delete the package. When deleting a stub
             // application we always set the enabled state to 'disabled'.