Fix GPU service and display initialization race.

services/ui/service.cc

Index: services/ui/service.cc
diff --git a/services/ui/service.cc b/services/ui/service.cc
index 9861c2886a5aa73635db7bcaafba19162a122f76..795e8ba81ef0b9c54fd7c0d6426c251263e6d09c 100644
--- a/services/ui/service.cc
+++ b/services/ui/service.cc
@@ -193,8 +193,6 @@ void Service::OnStart() {
     touch_controller_.reset(
         new ws::TouchController(window_server_->display_manager()));
 
-  platform_screen_->Init(window_server_->display_manager());
-
   ime_server_.Init(context()->connector());
 }
 
@@ -228,6 +226,10 @@ bool Service::OnConnect(const service_manager::ServiceInfo& remote_info,
   return true;
 }
 
+void Service::StartDisplayInit() {
+  platform_screen_->Init(window_server_->display_manager());
+}
+
 void Service::OnFirstDisplayReady() {
   PendingRequests requests;
   requests.swap(pending_requests_);