Delay setting hidden until after isVisibleNow test.

Setting hidden prior to test guarantees the test will fail. This
then causes the exit animation to not be loaded and consequently
the window is immediately hidden. Then, when the window is removed
later it reappears in order to animate away. The consequent flash
is undesirable.

Bug: 7242373 fixed.
Change-Id: I56966bd9060124be372702090f86b29b4deea8c0

Author: Craig Mautner

services/java/com/android/server/wm/WindowManagerService.java

@@ -3639,8 +3639,6 @@ public void removeWindowToken(IBinder token) {
             if (wtoken != null) {
                 boolean delayed = false;
                 if (!wtoken.hidden) {
-                    wtoken.hidden = true;
-
                     final int N = wtoken.windows.size();
                     boolean changed = false;
 
@@ -3661,6 +3659,8 @@ public void removeWindowToken(IBinder token) {
                         }
                     }
 
+                    wtoken.hidden = true;
+
                     if (changed) {
                         performLayoutAndPlaceSurfacesLocked();
                         updateFocusedWindowLocked(UPDATE_FOCUS_NORMAL,