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pkg/front_end/lib/src/fasta/source/diet_listener.dart

 // Copyright (c) 2016, 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 fasta.diet_listener;
 
 import 'package:front_end/src/fasta/kernel/kernel_ast_factory.dart'
     show KernelAstFactory;
 
 import 'package:front_end/src/fasta/type_inference/type_inference_engine.dart'
@@ skipping 30 matching lines @@
 
 import 'source_library_builder.dart' show SourceLibraryBuilder;
 
 class DietListener extends StackListener {
   final SourceLibraryBuilder library;
 
   final ClassHierarchy hierarchy;
 
   final CoreTypes coreTypes;
 
-  final bool isDartLibrary;
+  final bool enableNative;
 
   final TypeInferenceEngine typeInferenceEngine;
 
   ClassBuilder currentClass;
 
   /// For top-level declarations, this is the library scope. For class members,
   /// this is the instance scope of [currentClass].
   Scope memberScope;
 
   @override
   Uri uri;
 
   DietListener(SourceLibraryBuilder library, this.hierarchy, this.coreTypes,
       this.typeInferenceEngine)
       : library = library,
         uri = library.fileUri,
         memberScope = library.scope,
-        isDartLibrary = library.uri.scheme == "dart";
+        enableNative = (library.uri.scheme == "dart" || library.isPatch);
 
   void discard(int n) {
     for (int i = 0; i < n; i++) {
       pop();
     }
   }
 
   @override
   void endMetadataStar(int count, bool forParameter) {
     debugEvent("MetadataStar");
@@ skipping 413 matching lines @@
   @override
   void endNamedMixinApplication(Token beginToken, Token classKeyword,
       Token equals, Token implementsKeyword, Token endToken) {
     debugEvent("NamedMixinApplication");
     pop(); // Name.
     checkEmpty(beginToken.charOffset);
   }
 
   @override
   Token handleUnrecoverableError(Token token, FastaMessage message) {
-    if (isDartLibrary && message.code == codeExpectedBlockToSkip) {
+    if (enableNative && message.code == codeExpectedBlockToSkip) {
       Token recover = library.loader.target.skipNativeClause(token);
       if (recover != null) return recover;
     }
     return super.handleUnrecoverableError(token, message);
   }
 
   @override
   Link<Token> handleMemberName(Link<Token> identifiers) {
-    if (!isDartLibrary || identifiers.isEmpty) return identifiers;
+    if (!enableNative || identifiers.isEmpty) return identifiers;
     return removeNativeClause(identifiers);
   }
 
   AsyncMarker getAsyncMarker(StackListener listener) => listener.pop();
 
   void parseFunctionBody(StackListener listener, Token token, MemberKind kind) {
     try {
       Parser parser = new Parser(listener);
       token = parser.parseFormalParametersOpt(token, kind);
       var formals = listener.pop();
@@ skipping 59 matching lines @@
       return inputError(uri, token.charOffset, "Duplicated name: $name");
     }
     return builder;
   }
 
   @override
   void debugEvent(String name) {
     // printEvent(name);
   }
 }