Fix typo 2

tools/testing/dart/test_suite.dart

 // Copyright (c) 2012, 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.
 
 /**
  * Classes and methods for enumerating and preparing tests.
  *
  * This library includes:
  *
  * - Creating tests by listing all the Dart files in certain directories,
@@ skipping 1059 matching lines @@
    */
   static void copyFile(File source, File dest) {
     List contents = source.readAsBytesSync();
     RandomAccessFile handle = dest.openSync(FileMode.WRITE);
     handle.writeListSync(contents, 0, contents.length);
     handle.closeSync();
   }
 
   static String executableSuffix(String executable) {
     if (new Platform().operatingSystem() == 'windows') {
-      if (executable == 'd8' || executable == 'vm' || executable = 'none') {
+      if (executable == 'd8' || executable == 'vm' || executable == 'none') {
         return '.exe';
       } else {
         return '.bat';
       }
     }
     return '';
   }
 
   static String executableName(Map configuration) {
     String suffix = executableSuffix(configuration['compiler']);
@@ skipping 143 matching lines @@
  * $noCrash tests are expected to be flaky but not crash
  * $pass tests are expected to pass
  * $failOk tests are expected to fail that we won't fix
  * $fail tests are expected to fail that we should fix
  * $crash tests are expected to crash that we should fix
  * $timeout tests are allowed to timeout
 """;
     print(report);
    }
 }