Create code and instruction object, and install them in the background compilation thread while br…

runtime/vm/thread_registry.h

Index: runtime/vm/thread_registry.h
diff --git a/runtime/vm/thread_registry.h b/runtime/vm/thread_registry.h
index 20f4d95d55da3a53a40d95ba0fc4afce8405145c..b78a7615fa80ac0ac8bea0e555ec11aa8c1f33b9 100644
--- a/runtime/vm/thread_registry.h
+++ b/runtime/vm/thread_registry.h
@@ -48,6 +48,8 @@ class ThreadRegistry {
     CheckSafepointLocked();
   }
 
+  bool AtSafepoint() const { return in_rendezvous_; }
+
   bool RestoreStateTo(Thread* thread, Thread::State* state,
                       bool bypass_safepoint) {
     MonitorLocker ml(monitor_);