Minor cleanup

lib/android/app/src/main/java/com/reactnativenavigation/viewcontrollers/ParentController.java

 
 import java.util.Collection;
 
+import static com.reactnativenavigation.utils.CollectionUtils.forEach;
+
 public abstract class ParentController<T extends ViewGroup> extends ChildController {
 
 	public ParentController(Activity activity, ChildControllersRegistry childRegistry, String id, Presenter presenter, Options initialOptions) {
     @Override
     public void setDefaultOptions(Options defaultOptions) {
 	    super.setDefaultOptions(defaultOptions);
-        Collection<? extends ViewController> children = getChildControllers();
-        if (!CollectionUtils.isNullOrEmpty(children)) {
-            for (ViewController child : children) {
-                child.setDefaultOptions(defaultOptions);
-            }
-        }
+	    forEach(getChildControllers(), (child) -> child.setDefaultOptions(defaultOptions));
     }
 
     @Override

playground/android/app/src/main/java/com/reactnativenavigation/playground/MainActivity.java

 package com.reactnativenavigation.playground;
 
-import android.content.Intent;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.widget.ImageView;
         img.setImageDrawable(getDrawable(R.drawable.ic_android));
         setContentView(img);
     }
-
-    @Override
-    public void onWindowFocusChanged(boolean hasFocus) {
-        dismissSystemAlertsToPreventDetoxFromTimingOut(hasFocus);
-    }
-
-    private void dismissSystemAlertsToPreventDetoxFromTimingOut(boolean hasFocus) {
-        if (! hasFocus) {
-            sendBroadcast(new Intent(Intent.ACTION_CLOSE_SYSTEM_DIALOGS));
-        }
-    }
 }