Fix adding displays in mustash.

services/ui/ws/display.cc

Index: services/ui/ws/display.cc
diff --git a/services/ui/ws/display.cc b/services/ui/ws/display.cc
index f93023e760f6d12297b55f36060382a8811c90e2..8a27a90000c6f03588569b0d178514e647c054c6 100644
--- a/services/ui/ws/display.cc
+++ b/services/ui/ws/display.cc
@@ -250,6 +250,7 @@ void Display::InitWindowManagerDisplayRootsIfNecessary() {
   } else {
     CreateWindowManagerDisplayRootsFromFactories();
   }
+  display_manager()->OnDisplayUpdate(this);
 }
 
 void Display::CreateWindowManagerDisplayRootsFromFactories() {
@@ -322,7 +323,8 @@ void Display::OnViewportMetricsChanged(const ViewportMetrics& old_metrics,
     for (auto& pair : window_manager_display_root_map_)
       pair.second->root()->SetBounds(new_bounds);
   }
-  display_manager()->OnDisplayUpdate(this);
+  if (init_called_)
+    display_manager()->OnDisplayUpdate(this);
 }
 
 void Display::OnCompositorFrameDrawn() {