Resynthesize mixins from Kernel.

pkg/kernel/lib/ast.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.
 
 /// -----------------------------------------------------------------------
 ///                           ERROR HANDLING
 /// -----------------------------------------------------------------------
 ///
 /// As a rule of thumb, errors that can be detected statically are handled by
 /// the frontend, typically by translating the erroneous code into a 'throw' or
@@ skipping 598 matching lines @@
   /// Name of the class.
   ///
   /// Must be non-null and must be unique within the library.
   ///
   /// The name may contain characters that are not valid in a Dart identifier,
   /// in particular, the symbol '&' is used in class names generated for mixin
   /// applications.
   String name;
   bool isAbstract;
 
+  /// Whether this class is a synthetic implementation created for each
+  /// mixed-in class. For example the following code:
+  /// class Z extends A with B, C, D {}
+  /// class A {}
+  /// class B {}
+  /// class C {}
+  /// class D {}
+  /// ...creates:
+  /// abstract class A&B extends A mixedIn B {}
+  /// abstract class A&B&C extends A&B mixedIn C {}
+  /// abstract class A&B&C&D extends A&B&C mixedIn D {}
+  /// class Z extends A&B&C&D {}
+  /// All X&Y classes are marked as synthetic.
+  bool isSyntheticMixinImplementation;
+
   /// The uri of the source file this class was loaded from.
   String fileUri;
 
   final List<TypeParameter> typeParameters;
 
   /// The immediate super type, or `null` if this is the root class.
   Supertype supertype;
 
   /// The mixed-in type if this is a mixin application, otherwise `null`.
   Supertype mixedInType;
@@ skipping 10 matching lines @@
   final List<Constructor> constructors;
 
   /// Procedures declared in the class.
   ///
   /// For mixin applications this should be empty.
   final List<Procedure> procedures;
 
   Class(
       {this.name,
       this.isAbstract: false,
+      this.isSyntheticMixinImplementation: false,
       this.supertype,
       this.mixedInType,
       List<TypeParameter> typeParameters,
       List<Supertype> implementedTypes,
       List<Constructor> constructors,
       List<Procedure> procedures,
       List<Field> fields,
       this.fileUri,
       Reference reference})
       : this.typeParameters = typeParameters ?? <TypeParameter>[],
@@ skipping 3992 matching lines @@
   if (typedef_.canonicalName == null) {
     throw '$typedef_ has no canonical name';
   }
   return typedef_.canonicalName;
 }
 
 /// Annotation describing information which is not part of Dart semantics; in
 /// other words, if this information (or any information it refers to) changes,
 /// static analysis and runtime behavior of the library are unaffected.
 const informative = null;