Merge "Skip updating stack config if it is detached from a display" into pi-dev

services/core/java/com/android/server/am/ActivityStackSupervisor.java

@@ -1634,6 +1634,8 @@ public class ActivityStackSupervisor extends ConfigurationContainer implements D
      * @param markFrozenIfConfigChanged Whether to set {@link ActivityRecord#frozenBeforeDestroy} to
      *                                  {@code true} if config changed.
      * @param deferResume Whether to defer resume while updating config.
+     * @return 'true' if starting activity was kept or wasn't provided, 'false' if it was relaunched
+     *         because of configuration update.
      */
     boolean ensureVisibilityAndConfig(ActivityRecord starting, int displayId,
             boolean markFrozenIfConfigChanged, boolean deferResume) {
@@ -1644,6 +1646,11 @@ public class ActivityStackSupervisor extends ConfigurationContainer implements D
         ensureActivitiesVisibleLocked(null /* starting */, 0 /* configChanges */,
                 false /* preserveWindows */, false /* notifyClients */);
 
+        if (displayId == INVALID_DISPLAY) {
+            // The caller didn't provide a valid display id, skip updating config.
+            return true;
+        }
+
         // Force-update the orientation from the WindowManager, since we need the true configuration
         // to send to the client now.
         final Configuration config = mWindowManager.updateOrientationFromAppTokens(