VIMS: Clarify NonNullability of PackageMonitor#onPackageModified.

Bug: 178410946
Test: builds
Change-Id: I767e0f7f4ed1ae8c7f0a74afb5114a85a679d86a

core/java/com/android/internal/content/PackageMonitor.java

@@ -16,6 +16,7 @@
 
 package com.android.internal.content;
 
+import android.annotation.NonNull;
 import android.app.Activity;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.content.Context;
@@ -234,7 +235,7 @@ public abstract class PackageMonitor extends android.content.BroadcastReceiver {
     /**
      * Called when an existing package is updated or its disabled state changes.
      */
-    public void onPackageModified(String packageName) {
+    public void onPackageModified(@NonNull String packageName) {
     }
     
     public boolean didSomePackagesChange() {

services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerService.java

@@ -1782,7 +1782,7 @@ public class VoiceInteractionManagerService extends SystemService {
             }
 
             @Override
-            public void onPackageModified(String pkgName) {
+            public void onPackageModified(@NonNull String pkgName) {
                 // If the package modified is not in the current user, then don't bother making
                 // any changes as we are going to do any initialization needed when we switch users.
                 if (mCurUser != getChangingUserId()) {