Don't crash on deserialized type inference.

pkg/compiler/lib/src/inferrer/inferrer_visitor.dart

Index: pkg/compiler/lib/src/inferrer/inferrer_visitor.dart
diff --git a/pkg/compiler/lib/src/inferrer/inferrer_visitor.dart b/pkg/compiler/lib/src/inferrer/inferrer_visitor.dart
index 78ef6bb3c3a206fd60075ff8c4c0bda5471e227a..65e7439aa4e42047685a2d3700f80e9bd5c27c29 100644
--- a/pkg/compiler/lib/src/inferrer/inferrer_visitor.dart
+++ b/pkg/compiler/lib/src/inferrer/inferrer_visitor.dart
@@ -741,7 +741,10 @@ abstract class InferrerVisitor<T, E extends MinimalInferrerEngine<T>>
       : this.analyzedElement = analyzedElement,
         this.locals = handler {
     if (handler != null) return;
-    Node node = analyzedElement.node;
+    Node node;
+    if (resolvedAst.kind == ResolvedAstKind.PARSED) {
+      node = resolvedAst.node;
+    }
     FieldInitializationScope<T> fieldScope =
         analyzedElement.isGenerativeConstructor
             ? new FieldInitializationScope<T>(types)