dart2js: run dartfmt on tests

tests/compiler/dart2js/diagnostic_reporter_helper.dart

 // Copyright (c) 2015, 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 dart2js.diagnostic_reporter.helper;
 
 import 'package:compiler/src/diagnostics/diagnostic_listener.dart';
 import 'package:compiler/src/diagnostics/messages.dart';
 import 'package:compiler/src/diagnostics/spannable.dart';
 import 'package:compiler/src/diagnostics/source_span.dart';
 import 'package:compiler/src/elements/elements.dart';
 import 'options_helper.dart';
 
 abstract class DiagnosticReporterWrapper extends DiagnosticReporter {
   DiagnosticReporter get reporter;
 
   @override
-  DiagnosticMessage createMessage(
-      Spannable spannable,
-      MessageKind messageKind,
+  DiagnosticMessage createMessage(Spannable spannable, MessageKind messageKind,
       [Map arguments = const {}]) {
     return reporter.createMessage(spannable, messageKind, arguments);
   }
 
   @override
   internalError(Spannable spannable, message) {
     return reporter.internalError(spannable, message);
   }
 
   @override
   void log(message) {
     return reporter.log(message);
   }
 
   @override
   DiagnosticOptions get options => reporter.options;
 
   @override
-  void reportError(
-      DiagnosticMessage message,
-      [List<DiagnosticMessage> infos = const <DiagnosticMessage> []]) {
+  void reportError(DiagnosticMessage message,
+      [List<DiagnosticMessage> infos = const <DiagnosticMessage>[]]) {
     reporter.reportError(message, infos);
   }
 
   @override
-  void reportHint(
-      DiagnosticMessage message,
-      [List<DiagnosticMessage> infos = const <DiagnosticMessage> []]) {
+  void reportHint(DiagnosticMessage message,
+      [List<DiagnosticMessage> infos = const <DiagnosticMessage>[]]) {
     reporter.reportHint(message, infos);
   }
 
   @override
-  void reportInfo(
-      Spannable node,
-      MessageKind errorCode,
+  void reportInfo(Spannable node, MessageKind errorCode,
       [Map arguments = const {}]) {
     reporter.reportInfo(node, errorCode, arguments);
   }
 
   @override
-  void reportWarning(
-      DiagnosticMessage message,
-      [List<DiagnosticMessage> infos = const <DiagnosticMessage> []]) {
+  void reportWarning(DiagnosticMessage message,
+      [List<DiagnosticMessage> infos = const <DiagnosticMessage>[]]) {
     reporter.reportWarning(message, infos);
   }
 
   @override
   SourceSpan spanFromSpannable(Spannable node) {
     return reporter.spanFromSpannable(node);
   }
 
   @override
   withCurrentElement(Element element, f()) {
     return reporter.withCurrentElement(element, f);
   }
 
   @override
   bool get hasReportedError => reporter.hasReportedError;
 }