Make event-targeting asynchronous in window server.

services/ui/ws/test_utils.h

Index: services/ui/ws/test_utils.h
diff --git a/services/ui/ws/test_utils.h b/services/ui/ws/test_utils.h
index dc2803dd8fa216b48d3b7ec9070a5b474b5ac5eb..06568a5af311e13c8efa731a6c256a16cf54f669 100644
--- a/services/ui/ws/test_utils.h
+++ b/services/ui/ws/test_utils.h
@@ -233,19 +233,22 @@ class WindowManagerStateTestApi {
   }
 
   WindowTree* tree_awaiting_input_ack() {
-    return wms_->in_flight_event_details_ ? wms_->in_flight_event_details_->tree
-                                          : nullptr;
+    return wms_->in_flight_event_dispatch_details_
+               ? wms_->in_flight_event_dispatch_details_->tree
+               : nullptr;
   }
 
+  bool event_queue_empty() { return wms_->event_queue_.empty(); }
+
   const std::vector<std::unique_ptr<WindowManagerDisplayRoot>>&
   window_manager_display_roots() const {
     return wms_->window_manager_display_roots_;
   }
 
   bool AckInFlightEvent(mojom::EventResult result) {
-    if (!wms_->in_flight_event_details_)
+    if (!wms_->in_flight_event_dispatch_details_)
       return false;
-    wms_->OnEventAck(wms_->in_flight_event_details_->tree, result);
+    wms_->OnEventAck(wms_->in_flight_event_dispatch_details_->tree, result);
     return true;
   }