Formatter: keep a right parenthesis ')' with the last argument.

pkg/analyzer/lib/src/services/formatter_impl.dart

 // Copyright (c) 2013, 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 formatter_impl;
 
 import 'dart:math';
 
 import 'package:analyzer/analyzer.dart';
 import 'package:analyzer/src/generated/parser.dart';
@@ skipping 407 matching lines @@
     visit(node.name);
     token(node.period);
     visit(node.constructorName);
     visit(node.arguments);
   }
 
   visitArgumentList(ArgumentList node) {
     token(node.leftParenthesis);
     breakableNonSpace();
     visitCommaSeparatedNodes(node.arguments);
-    breakableNonSpace();
     token(node.rightParenthesis);
   }
 
   visitAsExpression(AsExpression node) {
     visit(node.expression);
     space();
     token(node.asOperator);
     space();
     visit(node.type);
   }
@@ skipping 1339 matching lines @@
     var lastLine =
         lineInfo.getLocation(lastOffset).lineNumber;
     var currentLine =
         lineInfo.getLocation(currentOffset).lineNumber;
     return currentLine - lastLine;
   }
 
   String toString() => writer.toString();
 
 }