smoke: support named argument in annotations

pkg/smoke/lib/codegen/recorder.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.
 
 /// Records accesses to Dart program declarations and generates code that will
 /// allow to do the same accesses at runtime using `package:smoke/static.dart`.
 /// Internally, this library relies on the `analyzer` to extract data from the
 /// program, and then uses [SmokeCodeGenerator] to produce the code needed by
 /// the smoke system.
 ///
@@ skipping 241 matching lines @@
   /// library.
   ConstExpression _convertAnnotation(Annotation annotation) {
     var element = annotation.element;
     if (element is ConstructorElement) {
       if (!element.name.isEmpty) {
         throw new UnimplementedError(
             'named constructors are not implemented in smoke.codegen.recorder');
       }
 
       var positionalArgs = [];
+      var namedArgs = {};
       for (var arg in annotation.arguments.arguments) {
         if (arg is NamedExpression) {
-          throw new UnimplementedError(
-              'named arguments in constructors are not implemented in '
-              'smoke.codegen.recorder');
+          namedArgs[arg.name.label.name] = _convertExpression(arg.expression);
+        } else {
+          positionalArgs.add(_convertExpression(arg));
         }
-        positionalArgs.add(_convertExpression(arg));
       }
 
       return new ConstructorExpression(importUrlFor(element.library),
-          element.enclosingElement.name, positionalArgs, const {});
+          element.enclosingElement.name, positionalArgs, namedArgs);
     }
 
     if (element is PropertyAccessorElement) {
       return new TopLevelIdentifier(
           importUrlFor(element.library), element.name);
     }
 
     throw new UnsupportedError('unsupported annotation $annotation');
   }
 
@@ skipping 104 matching lines @@
       this.includeInherited: true,
       this.includeUpTo: null,
       this.excludeFinal: false,
       this.includeMethods: false,
       this.withAnnotations: null,
       this.matches: null});
 }
 
 /// Predicate that tells whether [name] should be included in query results.
 typedef bool NameMatcher(String name);