Add failure case for manifest file testing.

chrome/test/data/nacl/manifest_file/irt_manifest_file_test.html

Index: chrome/test/data/nacl/manifest_file/irt_manifest_file_test.html
diff --git a/chrome/test/data/nacl/manifest_file/irt_manifest_file_test.html b/chrome/test/data/nacl/manifest_file/irt_manifest_file_test.html
index be9df7111c0c038a55c43894af7b8492979e586e..49452486da5dd4c2a2e86fe49ecab8f1b08c8250 100644
--- a/chrome/test/data/nacl/manifest_file/irt_manifest_file_test.html
+++ b/chrome/test/data/nacl/manifest_file/irt_manifest_file_test.html
@@ -40,7 +40,12 @@ function setupTests(tester, plugin) {
   tester.addAsyncTest('Test_00_Init', function(status) {
     plugin.addEventListener('message', function(message_event) {
       this.removeEventListener('message', arguments.callee, false);
-      var golden = 'File Contents:\nTest File Content';
+      var golden = [
+          'File Contents:\nTest File Content',
+          // 2 is an error code for ENOENT.

[Mark Seaborn, 2014/05/29 16:55:48]

Hard-coding a numeric errno value here isn't very clean.  It would be better if
you could just check for a result like "passed" here.  See other comment.

[hidehiko, 2014/05/30 04:49:58]

Done.

+          'open_resource() result: 2',
+          'open_resource() result: 2',
+      ];
       status.assertEqual(message_event.data, golden);
       status.pass();
     }, false);