am f8763581: Allow navigation bar drawing during window animations

* commit 'f87635813cabbf4f7dc0236fffc6b07a2715aff3':
  Allow navigation bar drawing during window animations
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/NavigationBarView.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/NavigationBarView.java
index f40f5016..416fb36 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/NavigationBarView.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/NavigationBarView.java
@@ -40,6 +40,7 @@
 import android.view.Surface;
 import android.view.View;
 import android.view.ViewGroup;
+import android.view.ViewRootImpl;
 import android.view.WindowManager;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.FrameLayout;
@@ -184,6 +185,15 @@
         mBarTransitions = new NavigationBarTransitions(this);
     }
 
+    @Override
+    protected void onAttachedToWindow() {
+        super.onAttachedToWindow();
+        ViewRootImpl root = getViewRootImpl();
+        if (root != null) {
+            root.setDrawDuringWindowsAnimating(true);
+        }
+    }
+
     public BarTransitions getBarTransitions() {
         return mBarTransitions;
     }