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

pkg/analyzer/lib/src/summary/public_namespace_computer.dart

Index: pkg/analyzer/lib/src/summary/public_namespace_computer.dart
diff --git a/pkg/analyzer/lib/src/summary/public_namespace_computer.dart b/pkg/analyzer/lib/src/summary/public_namespace_computer.dart
index 203043a1b9528b1f147f23169e124e1851c96334..b11701b1229111a7d3e7d99727142d9b526325eb 100644
--- a/pkg/analyzer/lib/src/summary/public_namespace_computer.dart
+++ b/pkg/analyzer/lib/src/summary/public_namespace_computer.dart
@@ -177,6 +177,12 @@ class _PublicNamespaceVisitor extends RecursiveAstVisitor {
   }
 
   @override
+  visitGenericTypeAlias(GenericTypeAlias node) {
+    addNameIfPublic(node.name.name, ReferenceKind.genericFunctionTypedef,
+        node.typeParameters?.typeParameters?.length ?? 0);
+  }
+
+  @override
   visitPartDirective(PartDirective node) {
     parts.add(node.uri.stringValue ?? '');
   }