[CodeAction] Convert lambda to delegate action no longer puts a

redundant () in the anonymous delegate.

ICSharpCode.NRefactory.CSharp/Ast/Expressions/AnonymousMethodExpression.cs

@@ -80,6 +80,7 @@ namespace ICSharpCode.NRefactory.CSharp
 		public AnonymousMethodExpression (BlockStatement body, IEnumerable<ParameterDeclaration> parameters = null)
 		{
 			if (parameters != null) {
+				hasParameterList = true;
 				foreach (var parameter in parameters) {
 					AddChild (parameter, Roles.Parameter);
 				}

ICSharpCode.NRefactory.CSharp/Refactoring/CodeActions/ConvertLambdaToAnonymousDelegateAction.cs

@@ -56,7 +56,6 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 					};
 				}
 				var method = new AnonymousMethodExpression (newBody, GetParameters(lambdaResolveResult.Parameters, context));
-				method.HasParameterList = true;
 				script.Replace(node, method);
 			});
 		}
@@ -64,6 +63,9 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 
 		IEnumerable<ParameterDeclaration> GetParameters(IList<IParameter> parameters, RefactoringContext context)
 		{
+			if (parameters == null || parameters.Count == 0)
+				return null;
+			var result = new List<ParameterDeclaration> ();
 			foreach (var parameter in parameters) {
 				var type = context.CreateShortType(parameter.Type);
 				var name = parameter.Name;
@@ -72,8 +74,9 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 					modifier |= ParameterModifier.Ref;
 				if (parameter.IsOut)
 					modifier |= ParameterModifier.Out;
-				yield return new ParameterDeclaration(type, name, modifier);
+				result.Add (new ParameterDeclaration(type, name, modifier));
 			}
+			return result;
 		}
 	}
 }

ICSharpCode.NRefactory.Tests/CSharp/CodeActions/ConvertLamdaToAnonymousDelegateTests.cs

@@ -72,6 +72,28 @@ class A
 	System.Console.WriteLine (i1);
 };
 	}
+}");
+		}
+
+		[Test]
+		public void ParameterLessLambdaTest ()
+		{
+			Test<ConvertLambdaToAnonymousDelegateAction>(@"
+class A
+{
+	void F ()
+	{
+		System.Action = ()$ => { System.Console.WriteLine (); };
+	}
+}", @"
+class A
+{
+	void F ()
+	{
+		System.Action = delegate {
+	System.Console.WriteLine ();
+};
+	}
 }");
 		}
 	}