Make no-location redirect response to be "opaque redirect" when redirect mode is manual.

third_party/WebKit/LayoutTests/external/wpt/fetch/api/redirect/redirect-location.js

 if (this.document === undefined) {
   importScripts("/resources/testharness.js");
   importScripts("../resources/utils.js");
 }
 
 function redirectLocation(desc, redirectUrl, redirectLocation, redirectStatus, redirectMode, shouldPass) {
   var url = redirectUrl;
   var urlParameters = "?redirect_status=" + redirectStatus;
   if (redirectLocation)
     urlParameters += "&location=" + encodeURIComponent(redirectLocation);
 
   var requestInit = {"redirect": redirectMode};
 
   promise_test(function(test) {
     if (redirectMode === "error" || !shouldPass)
       return promise_rejects(test, new TypeError(), fetch(url + urlParameters, requestInit));
-    if (redirectLocation && redirectMode === "manual")
+    if (redirectMode === "manual")
       return fetch(url + urlParameters, requestInit).then(function(resp) {
         assert_equals(resp.status, 0, "Response's status is 0");
         assert_equals(resp.type, "opaqueredirect", "Response's type is opaqueredirect");
         assert_equals(resp.statusText, "", "Response's statusText is \"\"");
         assert_true(resp.headers.entries().next().done, "Headers should be empty");
       });
 
-    if (redirectMode === "manual" || redirectMode === "follow")
+    if (redirectMode === "follow")
       return fetch(url + urlParameters, requestInit).then(function(resp) {
         assert_equals(resp.status, redirectStatus, "Response's status is " + redirectStatus);
       });
     assert_unreached(redirectMode + " is not a valid redirect mode");
   }, desc);
 }
 
 var redirUrl = RESOURCES_DIR + "redirect.py";
 var locationUrl = "top.txt";
 var invalidLocationUrl = "#invalidurl:";
 var dataLocationUrl = "data:,data%20url";
 // FIXME: We may want to mix redirect-mode and cors-mode.
 // FIXME: Add tests for "error" redirect-mode.
 for (var statusCode of [301, 302, 303, 307, 308]) {
   redirectLocation("Redirect " + statusCode + " in \"follow\" mode without location", redirUrl, undefined, statusCode, "follow", true);
   redirectLocation("Redirect " + statusCode + " in \"manual\" mode without location", redirUrl, undefined, statusCode, "manual", true);
 
   redirectLocation("Redirect " + statusCode + " in \"follow\" mode with invalid location", redirUrl, invalidLocationUrl, statusCode, "follow", false);
   redirectLocation("Redirect " + statusCode + " in \"manual\" mode with invalid location", redirUrl, invalidLocationUrl, statusCode, "manual", true);
 
   redirectLocation("Redirect " + statusCode + " in \"follow\" mode with data location", redirUrl, dataLocationUrl, statusCode, "follow", false);
   redirectLocation("Redirect " + statusCode + " in \"manual\" mode with data location", redirUrl, dataLocationUrl, statusCode, "manual", true);
 }
 
 done();