Fix for summarization of generic function type aliases and support for resynthesizing.

pkg/analyzer/test/src/summary/element_text.dart

 // Copyright (c) 2017, 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.
 
 import 'dart:io';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
@@ skipping 424 matching lines @@
 
     writeBodyModifiers(e);
 
     buffer.writeln(' {}');
   }
 
   void writeFunctionTypeAliasElement(FunctionTypeAliasElement e) {
     writeDocumentation(e);
     writeMetadata(e, '', '\n');
 
-    buffer.write('typedef ');
-    writeType2(e.returnType);
+    if (e is GenericTypeAliasElement) {
+      buffer.write('typedef ');
+      writeName(e);
+      writeTypeParameterElements(e.typeParameters);
 
-    writeName(e);
+      buffer.write(' = ');
 
-    writeTypeParameterElements(e.typeParameters);
-    writeParameterElements(e.parameters);
+      writeType(e.function.returnType);
+      buffer.write(' Function');
+      writeTypeParameterElements(e.function.typeParameters);
+      writeParameterElements(e.function.parameters);
+    } else {
+      buffer.write('typedef ');
+      writeType2(e.returnType);
+
+      writeName(e);
+
+      writeTypeParameterElements(e.typeParameters);
+      writeParameterElements(e.parameters);
+    }
 
     buffer.writeln(';');
   }
 
   void writeIf(bool flag, String str) {
     if (flag) {
       buffer.write(str);
     }
   }
 
@@ skipping 342 matching lines @@
     return components.join(';');
   }
 }
 
 class _Replacement {
   final int offset;
   final int end;
   final String text;
   _Replacement(this.offset, this.end, this.text);
 }