Refactor parseType in preparation for bigger changes.

pkg/kernel/lib/text/ast_to_text.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 kernel.ast_to_text;
 
 import '../ast.dart';
 import '../import_table.dart';
 
 class Namer<T> {
   int index = 0;
@@ skipping 1380 matching lines @@
 
   visitVariableDeclaration(VariableDeclaration node) {
     writeIndentation();
     writeVariableDeclaration(node, useVarKeyword: true);
     endLine(';');
   }
 
   visitFunctionDeclaration(FunctionDeclaration node) {
     writeIndentation();
     writeWord('function');
-    writeFunction(node.function, name: getVariableName(node.variable));
+    if (node.function != null) {
+      writeFunction(node.function, name: getVariableName(node.variable));
+    } else {
+      writeWord(getVariableName(node.variable));
+      endLine('...;');
+    }
   }
 
   void writeVariableDeclaration(VariableDeclaration node,
       {bool useVarKeyword: false}) {
     if (showOffsets) writeWord("[${node.fileOffset}]");
     writeModifier(node.isFinal, 'final');
     writeModifier(node.isConst, 'const');
     if (node.type != null) {
       writeAnnotatedType(node.type, annotator?.annotateVariable(this, node));
     }
@@ skipping 243 matching lines @@
   }
   throw 'illegal ProcedureKind: $kind';
 }
 
 class ExpressionPrinter {
   final Printer writeer;
   final int minimumPrecedence;
 
   ExpressionPrinter(this.writeer, this.minimumPrecedence);
 }