Revert two Kernel changes that were causing test failures.

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 475 matching lines @@
   transformChildren(Transformer v) {}
 }
 
 /// Declaration of a type alias.
 class Typedef extends NamedNode {
   /// The uri of the source file that contains the declaration of this typedef.
   String fileUri;
   List<Expression> annotations = const <Expression>[];
   String name;
   final List<TypeParameter> typeParameters;
-
-  @informative
-  int requiredParameterCount = 0;
-
-  @informative
-  List<VariableDeclaration> positionalParameters = <VariableDeclaration>[];
-
-  @informative
-  List<VariableDeclaration> namedParameters = <VariableDeclaration>[];
-
   DartType type;
 
   Typedef(this.name, this.type,
       {Reference reference, this.fileUri, List<TypeParameter> typeParameters})
       : this.typeParameters = typeParameters ?? <TypeParameter>[],
         super(reference) {
     setParents(this.typeParameters, this);
   }
 
   Library get enclosingLibrary => parent;
 
   accept(TreeVisitor v) {
     return v.visitTypedef(this);
   }
 
-  void setParameters(
-      int requiredParameterCount,
-      List<VariableDeclaration> positionalParameters,
-      List<VariableDeclaration> namedParameters) {
-    this.requiredParameterCount = requiredParameterCount;
-    this.positionalParameters = positionalParameters;
-    this.namedParameters = namedParameters;
-    setParents(this.positionalParameters, this);
-    setParents(this.namedParameters, this);
-  }
-
   transformChildren(Transformer v) {
     transformList(annotations, v, this);
     transformList(typeParameters, v, this);
-    transformList(positionalParameters, v, this);
-    transformList(namedParameters, v, this);
     if (type != null) {
       type = v.visitDartType(type);
     }
   }
 
   visitChildren(Visitor v) {
     visitList(annotations, v);
     visitList(typeParameters, v);
-    visitList(typeParameters, v);
-    visitList(positionalParameters, v);
-    visitList(namedParameters, v);
     type?.accept(v);
   }
 
   void addAnnotation(Expression node) {
     if (annotations.isEmpty) {
       annotations = <Expression>[];
     }
     annotations.add(node);
     node.parent = this;
   }
@@ skipping 295 matching lines @@
 // ------------------------------------------------------------------------
 //                            MEMBERS
 // ------------------------------------------------------------------------
 
 abstract class Member extends NamedNode {
   /// End offset in the source file it comes from. Valid values are from 0 and
   /// up, or -1 ([TreeNode.noOffset]) if the file end offset is not available
   /// (this is the default if none is specifically set).
   int fileEndOffset = TreeNode.noOffset;
 
-  /// Documentation comment of the member, or `null`.
-  @informative
-  String documentationComment;
-
   /// List of metadata annotations on the member.
   ///
   /// This defaults to an immutable empty list. Use [addAnnotation] to add
   /// annotations if needed.
   List<Expression> annotations = const <Expression>[];
   Name name;
 
   /// Flags summarizing the kinds of AST nodes contained in this member, for
   /// speeding up transformations that only affect certain types of nodes.
   ///
@@ skipping 3829 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;