Add a test that server does not send errors when errors have been disabled

pkg/analysis_server/test/integration/integration_tests.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.
 
 library test.integration.analysis;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:convert';
 import 'dart:io';
@@ skipping 625 matching lines @@
    * Start the server.  If [debugServer] is `true`, the server will be started
    * with "--debug", allowing a debugger to be attached. If [profileServer] is
    * `true`, the server will be started with "--observe" and
    * "--pause-isolates-on-exit", allowing the observatory to be used.
    */
   Future start(
       {bool checked: true,
       bool debugServer: false,
       int diagnosticPort,
       bool enableNewAnalysisDriver: false,
+      bool noErrorNotification: false,
       bool profileServer: false,
       String sdkPath,
       int servicesPort,
       bool useAnalysisHighlight2: false}) {
     if (_process != null) {
       throw new Exception('Process already started');
     }
     _time.start();
     String dartBinary = Platform.executable;
     String rootDir =
@@ skipping 38 matching lines @@
     }
     if (sdkPath != null) {
       arguments.add('--sdk=$sdkPath');
     }
     if (useAnalysisHighlight2) {
       arguments.add('--useAnalysisHighlight2');
     }
     if (!enableNewAnalysisDriver) {
       arguments.add('--disable-new-analysis-driver');
     }
+    if (noErrorNotification) {
+      arguments.add('--no-error-notification');
+    }
 //    print('Launching $serverPath');
 //    print('$dartBinary ${arguments.join(' ')}');
     return Process.start(dartBinary, arguments).then((Process process) {
       _process = process;
       process.exitCode.then((int code) {
         if (code != 0) {
           _badDataFromServer('server terminated with exit code $code');
         }
       });
     });
@@ skipping 248 matching lines @@
   void populateMismatches(item, List<MismatchDescriber> mismatches);
 
   /**
    * Create a [MismatchDescriber] describing a mismatch with a simple string.
    */
   MismatchDescriber simpleDescription(String description) =>
       (Description mismatchDescription) {
         mismatchDescription.add(description);
       };
 }