Add support for |any| to Sky's code generator

sky/engine/tonic/dart_value.h

Index: sky/engine/tonic/dart_value.h
diff --git a/sky/engine/tonic/dart_value.h b/sky/engine/tonic/dart_value.h
index 57332e451b1f0ff110b430f82e114b3738b53773..2eac3a8e6e7254cc4ced90f974604e5d74c87d25 100644
--- a/sky/engine/tonic/dart_value.h
+++ b/sky/engine/tonic/dart_value.h
@@ -30,6 +30,10 @@ class DartValue : public RefCounted<DartValue> {
   ~DartValue();
 
   Dart_Handle dart_value() const { return dart_value_.value(); }
+  const base::WeakPtr<DartState>& dart_state() const {
+      return dart_value_.dart_state();
+  }
+
   bool is_empty() const { return !dart_value(); }
 
   bool is_null() const {