Store and serialize NativeBehavior in TreeElements.

pkg/compiler/lib/src/common/backend_api.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart2js.backend_api;
 
 import 'dart:async' show Future;
 
 import '../common.dart';
 import '../common/codegen.dart' show CodegenImpact;
@@ skipping 358 matching lines @@
 
   FunctionElement helperForMainArity() => null;
 
   void forgetElement(Element element) {}
 
   void registerMainHasArguments(Enqueuer enqueuer) {}
 
   void registerAsyncMarker(
       FunctionElement element, Enqueuer enqueuer, Registry registry) {}
 
-  /// Called when resolving a call to a foreign function.
-  void registerForeignCall(Send node, Element element,
+  /// Called when resolving a call to a foreign function. If a non-null value
+  /// is returned, this is stored as native data for [node] in the resolved
+  /// AST.
+  dynamic resolveForeignCall(Send node, Element element,
       CallStructure callStructure, ForeignResolver resolver) {}
 
   /// Returns the location of the patch-file associated with [libraryName]
   /// resolved from [plaformConfigUri].
   ///
   /// Returns null if there is none.
   Uri resolvePatchUri(String libraryName, Uri plaformConfigUri);
 
   /// Creates an impact strategy to use for compilation.
   ImpactStrategy createImpactStrategy(
@@ skipping 35 matching lines @@
   }
 }
 
 /// Interface for serialization of backend specific data.
 class BackendSerialization {
   const BackendSerialization();
 
   SerializerPlugin get serializer => const SerializerPlugin();
   DeserializerPlugin get deserializer => const DeserializerPlugin();
 }