From 38e5d9e797856b7f130ec35e43e33f6f43dcf70d Mon Sep 17 00:00:00 2001
From: Bishoy Gendy <bishoygendy@google.com>
Date: Tue, 1 Nov 2022 13:37:10 +0000
Subject: Require apps to be in forground to be able to scan

After seeing the history of this change and debugging it, now OKG
doesn't initiate a scanning request and the latest documention for media
router recommends removing to remove the MediaRouter Callback in onStop
method.

- By this change we are limiting scanning to apps in the foreground
while screen is on.

- Wrap the change inside of a feature flag to help toggling it off
later if problems started to be reported.

Bug: 254634785
Test: manually && atest MediaRouter2Test MediaRouterManagerTest
Change-Id: I2d56cf3b2775f55e0e6b110c145b77d1a436a1ed
---
 .../server/media/MediaRouter2ServiceImpl.java      | 29 +++++++++++++++++++---
 1 file changed, 25 insertions(+), 4 deletions(-)

diff --git a/services/core/java/com/android/server/media/MediaRouter2ServiceImpl.java b/services/core/java/com/android/server/media/MediaRouter2ServiceImpl.java
index 1998af649070..15586c4a055e 100644
--- a/services/core/java/com/android/server/media/MediaRouter2ServiceImpl.java
+++ b/services/core/java/com/android/server/media/MediaRouter2ServiceImpl.java
@@ -29,6 +29,7 @@ import android.Manifest;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.app.ActivityManager;
+import android.app.ActivityThread;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
@@ -51,6 +52,7 @@ import android.os.Looper;
 import android.os.PowerManager;
 import android.os.RemoteException;
 import android.os.UserHandle;
+import android.provider.DeviceConfig;
 import android.text.TextUtils;
 import android.util.ArrayMap;
 import android.util.Log;
@@ -89,10 +91,19 @@ class MediaRouter2ServiceImpl {
     // TODO: (In Android S or later) if we add callback methods for generic failures
     //       in MediaRouter2, remove this constant and replace the usages with the real request IDs.
     private static final long DUMMY_REQUEST_ID = -1;
-    private static final int PACKAGE_IMPORTANCE_FOR_DISCOVERY = IMPORTANCE_FOREGROUND_SERVICE;
 
     private static final int DUMP_EVENTS_MAX_COUNT = 70;
 
+    private static final String MEDIA_BETTER_TOGETHER_NAMESPACE = "media_better_together";
+
+    private static final String KEY_SCANNING_PACKAGE_MINIMUM_IMPORTANCE =
+            "scanning_package_minimum_importance";
+
+    private static int sPackageImportanceForScanning = DeviceConfig.getInt(
+            MEDIA_BETTER_TOGETHER_NAMESPACE,
+            /* name */ KEY_SCANNING_PACKAGE_MINIMUM_IMPORTANCE,
+            /* defaultValue */ IMPORTANCE_FOREGROUND_SERVICE);
+
     private final Context mContext;
     private final UserManagerInternal mUserManagerInternal;
     private final Object mLock = new Object();
@@ -140,7 +151,7 @@ class MediaRouter2ServiceImpl {
         mContext = context;
         mActivityManager = mContext.getSystemService(ActivityManager.class);
         mActivityManager.addOnUidImportanceListener(mOnUidImportanceListener,
-                PACKAGE_IMPORTANCE_FOR_DISCOVERY);
+                sPackageImportanceForScanning);
         mPowerManager = mContext.getSystemService(PowerManager.class);
         mUserManagerInternal = LocalServices.getService(UserManagerInternal.class);
 
@@ -149,6 +160,10 @@ class MediaRouter2ServiceImpl {
         screenOnOffIntentFilter.addAction(ACTION_SCREEN_OFF);
 
         mContext.registerReceiver(mScreenOnOffReceiver, screenOnOffIntentFilter);
+
+        DeviceConfig.addOnPropertiesChangedListener(MEDIA_BETTER_TOGETHER_NAMESPACE,
+                ActivityThread.currentApplication().getMainExecutor(),
+                this::onDeviceConfigChange);
     }
 
     // Start of methods that implement MediaRouter2 operations.
@@ -1386,6 +1401,12 @@ class MediaRouter2ServiceImpl {
 
     // End of locked methods that are used by both MediaRouter2 and MediaRouter2Manager.
 
+    private void onDeviceConfigChange(@NonNull DeviceConfig.Properties properties) {
+        sPackageImportanceForScanning = properties.getInt(
+                /* name */ KEY_SCANNING_PACKAGE_MINIMUM_IMPORTANCE,
+                /* defaultValue */ IMPORTANCE_FOREGROUND_SERVICE);
+    }
+
     static long toUniqueRequestId(int requesterId, int originalRequestId) {
         return ((long) requesterId << 32) | originalRequestId;
     }
@@ -2563,7 +2584,7 @@ class MediaRouter2ServiceImpl {
                 isManagerScanning = managerRecords.stream().anyMatch(manager ->
                         manager.mIsScanning && service.mActivityManager
                                 .getPackageImportance(manager.mPackageName)
-                                <= PACKAGE_IMPORTANCE_FOR_DISCOVERY);
+                                <= sPackageImportanceForScanning);
 
                 if (isManagerScanning) {
                     discoveryPreferences = routerRecords.stream()
@@ -2572,7 +2593,7 @@ class MediaRouter2ServiceImpl {
                 } else {
                     discoveryPreferences = routerRecords.stream().filter(record ->
                             service.mActivityManager.getPackageImportance(record.mPackageName)
-                                    <= PACKAGE_IMPORTANCE_FOR_DISCOVERY)
+                                    <= sPackageImportanceForScanning)
                             .map(record -> record.mDiscoveryPreference)
                             .collect(Collectors.toList());
                 }
-- 
cgit v1.2.3-59-g8ed1b