More generic function type cases working

pkg/analyzer/lib/src/dart/element/builder.dart

 // Copyright (c) 2014, 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 analyzer.src.dart.element.builder;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 438 matching lines @@
     SimpleIdentifier aliasName = node.name;
     List<TypeParameterElement> typeParameters = holder.typeParameters;
     GenericTypeAliasElementImpl element =
         new GenericTypeAliasElementImpl.forNode(aliasName);
     _setCodeRange(element, node);
     element.metadata = _createElementAnnotations(node.metadata);
     setElementDocumentationComment(element, node);
     element.typeParameters = typeParameters;
     _createTypeParameterTypes(typeParameters);
     element.type = new FunctionTypeImpl.forTypedef(element);
-    element.function = node.functionType.type.element;
+    element.function = node.functionType?.type?.element;
     _currentHolder.addTypeAlias(element);
     aliasName.staticElement = element;
     holder.validate();
     return null;
   }
 
   @override
   Object visitImportDirective(ImportDirective node) {
     List<ElementAnnotation> annotations =
         _createElementAnnotations(node.metadata);
@@ skipping 969 matching lines @@
     // visible range
     _setParameterVisibleRange(node, parameter);
     if (normalParameter is SimpleFormalParameter &&
         normalParameter.type == null) {
       parameter.hasImplicitType = true;
     }
     _currentHolder.addParameter(parameter);
     if (normalParameter is SimpleFormalParameterImpl) {
       normalParameter.element = parameter;
     }
-    parameterName.staticElement = parameter;
+    parameterName?.staticElement = parameter;
     normalParameter.accept(this);
     return null;
   }
 
   @override
   Object visitFunctionTypedFormalParameter(FunctionTypedFormalParameter node) {
     if (node.parent is! DefaultFormalParameter) {
       SimpleIdentifier parameterName = node.identifier;
       ParameterElementImpl parameter =
           new ParameterElementImpl.forNode(parameterName);
@@ skipping 208 matching lines @@
     return null;
   }
 
   /**
    * Return the lexical identifiers associated with the given [identifiers].
    */
   static List<String> _getIdentifiers(NodeList<SimpleIdentifier> identifiers) {
     return identifiers.map((identifier) => identifier.name).toList();
   }
 }