Add null check for AppOpsService

Bug: 369481502
Test: Manual.
(cherry picked from https://android-review.googlesource.com/q/commit:c89afa8417681984e8e76ec7a43df7d8a62e27e1)
Merged-In: I94e91b87f21290d2ea88d449c1461aaa6e2e6e10
Change-Id: I94e91b87f21290d2ea88d449c1461aaa6e2e6e10

NOTE FOR REVIEWERS - errors occurred while applying the patch.
PLEASE REVIEW CAREFULLY.
Errors:
Error applying patch in services/core/java/com/android/server/appop/AppOpsService.java, hunk HunkHeader[1032,6->1032,9]: Hunk cannot be applied

Original patch:
 From c89afa8417681984e8e76ec7a43df7d8a62e27e1 Mon Sep 17 00:00:00 2001
From: gang.huang <gang.huang@unisoc.com>
Date: Wed, 25 Sep 2024 15:01:11 +0800
Subject: [PATCH] Add null check for AppOpsService

Flag: EXEMPT bugfix
Bug: 369481502
Test: Manual.
Change-Id: I94e91b87f21290d2ea88d449c1461aaa6e2e6e10
---