Check CORS policy on redirect in TextTrackLoader

third_party/WebKit/LayoutTests/http/tests/security/text-track-crossorigin.html

Index: third_party/WebKit/LayoutTests/http/tests/security/text-track-crossorigin.html
diff --git a/third_party/WebKit/LayoutTests/http/tests/security/text-track-crossorigin.html b/third_party/WebKit/LayoutTests/http/tests/security/text-track-crossorigin.html
index f9d7f025d7bb165e83acdbf29302acafbeaa2d22..14c408dea236b0dd003679b4199099e09d8b1ac7 100644
--- a/third_party/WebKit/LayoutTests/http/tests/security/text-track-crossorigin.html
+++ b/third_party/WebKit/LayoutTests/http/tests/security/text-track-crossorigin.html
@@ -38,9 +38,20 @@
                     break;
 
                 case 3:
+                    log('Loading <b>without</b> Access-Control-Allow-Origin header, with a redirect, no "crossorigin" attribute on &lt;video&gt;');

[foolip, 2016/09/23 09:16:10]

So, the problem was that if the redirect response itself didn't have
Access-Control-Allow-Origin, we'd still happily use the resource redirected to
as long as that passes the CORS check?

[fs, 2016/09/23 10:22:42]

Isn't it a "same-origin request, cross-origin redirect" case?

+                    url = "http://127.0.0.1:8000/security/resources/redir.php?url=http://localhost:8000/security/resources/captions-with-access-control-headers.php"
+                    videoElement.removeAttribute('crossorigin');
+                    trackElement.removeAttribute('crossorigin');
+                    trackElement.setAttribute('src', url);
+                    shouldLoad = false;
+                    ++counter;
+                    break;
+
+                case 4:
                     log("END OF TEST");
                     if (window.testRunner)
                         testRunner.notifyDone();
+                    break;
                 }
             }
 
@@ -72,8 +83,13 @@
                     shouldLoad = true;
                     ++counter;
                     break;
-                }
 
+                case 4:
+                    log("END OF TEST");
+                    if (window.testRunner)
+                        testRunner.notifyDone();
+                    break;
+                }
             }
 
             function start()