Fixing MainThreadInitializedObject

> Making SafeCloseable implementation mandatory, to prevent leaks during test and preview
> Removing getNoCreate method and defining executeIfCreated to avoid null pointer exceptions
> Fixing sandbox value leaking into main, by Checking sandbox against App context
> Converting sanbox to an interface instead a class

Bug: 335280439
Test: Presubmit
Flag: None
Change-Id: I951dcde871898e745ff6490a1c4f8fd1512888f5

src/com/android/launcher3/util/ScreenOnTracker.java

@@ -27,7 +27,7 @@ import java.util.concurrent.CopyOnWriteArrayList;
 /**
  * Utility class for tracking if the screen is currently on or off
  */
-public class ScreenOnTracker {
+public class ScreenOnTracker implements SafeCloseable {
 
     public static final MainThreadInitializedObject<ScreenOnTracker> INSTANCE =
             new MainThreadInitializedObject<>(ScreenOnTracker::new);
@@ -35,14 +35,21 @@ public class ScreenOnTracker {
     private final SimpleBroadcastReceiver mReceiver = new SimpleBroadcastReceiver(this::onReceive);
     private final CopyOnWriteArrayList<ScreenOnListener> mListeners = new CopyOnWriteArrayList<>();
 
+    private final Context mContext;
     private boolean mIsScreenOn;
 
     private ScreenOnTracker(Context context) {
         // Assume that the screen is on to begin with
+        mContext = context;
         mIsScreenOn = true;
         mReceiver.register(context, ACTION_SCREEN_ON, ACTION_SCREEN_OFF, ACTION_USER_PRESENT);
     }
 
+    @Override
+    public void close() {
+        mReceiver.unregisterReceiverSafely(mContext);
+    }
+
     private void onReceive(Intent intent) {
         String action = intent.getAction();
         if (ACTION_SCREEN_ON.equals(action)) {