From 65a99b6158b56c94612d21002376861e01d87bd9 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <zhin@google.com>
Date: Mon, 1 Oct 2018 11:57:53 -0700
Subject: [PATCH] Change default mode for system alert window

Starting from Q, on Phones, SYSTEM_ALERT_WINDOW is by default denied for
all callers.

Bug: 63697002
Test: m, flash, boot
Change-Id: I7f2f697ce6cafb43b6e4075ad1985a9041605a0a
---
 core/java/android/app/AppOpsManager.java | 24 +++++++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/core/java/android/app/AppOpsManager.java b/core/java/android/app/AppOpsManager.java
index e155fe201f987..7ae88e6576383 100644
--- a/core/java/android/app/AppOpsManager.java
+++ b/core/java/android/app/AppOpsManager.java
@@ -27,6 +27,7 @@ import android.annotation.TestApi;
 import android.annotation.UnsupportedAppUsage;
 import android.app.usage.UsageStatsManager;
 import android.content.Context;
+import android.content.pm.PackageManager;
 import android.content.pm.ParceledListSlice;
 import android.database.ContentObserver;
 import android.media.AudioAttributes.AttributeUsage;
@@ -41,9 +42,9 @@ import android.os.RemoteException;
 import android.os.UserManager;
 import android.provider.Settings;
 import android.util.ArrayMap;
+import android.util.SparseArray;
 
 import com.android.internal.annotations.GuardedBy;
-import android.util.SparseArray;
 import com.android.internal.app.IAppOpsActiveCallback;
 import com.android.internal.app.IAppOpsCallback;
 import com.android.internal.app.IAppOpsNotedCallback;
@@ -60,8 +61,8 @@ import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
-import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.Executor;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Consumer;
 
 /**
@@ -1489,7 +1490,7 @@ public class AppOpsManager {
             AppOpsManager.MODE_ALLOWED, // READ_ICC_SMS
             AppOpsManager.MODE_ALLOWED, // WRITE_ICC_SMS
             AppOpsManager.MODE_DEFAULT, // WRITE_SETTINGS
-            AppOpsManager.MODE_DEFAULT, // SYSTEM_ALERT_WINDOW
+            getSystemAlertWindowDefault(), // SYSTEM_ALERT_WINDOW
             AppOpsManager.MODE_ALLOWED, // ACCESS_NOTIFICATIONS
             AppOpsManager.MODE_ALLOWED, // CAMERA
             AppOpsManager.MODE_ALLOWED, // RECORD_AUDIO
@@ -4807,4 +4808,21 @@ public class AppOpsManager {
             }
         }
     }
+
+    private static int getSystemAlertWindowDefault() {
+        final Context context = ActivityThread.currentApplication();
+        if (context == null) {
+            return AppOpsManager.MODE_DEFAULT;
+        }
+
+        // system alert window is disable on low ram phones starting from Q
+        final PackageManager pm = context.getPackageManager();
+        // TVs are constantly plugged in and has less concern for memory/power
+        if (ActivityManager.isLowRamDeviceStatic()
+                && !pm.hasSystemFeature(PackageManager.FEATURE_LEANBACK, 0)) {
+            return AppOpsManager.MODE_IGNORED;
+        }
+
+        return AppOpsManager.MODE_DEFAULT;
+    }
 }