Fix foreign fetch intercepting CORS preflighted requests if preflight was in cache.

third_party/WebKit/LayoutTests/http/tests/serviceworker/foreign-fetch-basics.html

Index: third_party/WebKit/LayoutTests/http/tests/serviceworker/foreign-fetch-basics.html
diff --git a/third_party/WebKit/LayoutTests/http/tests/serviceworker/foreign-fetch-basics.html b/third_party/WebKit/LayoutTests/http/tests/serviceworker/foreign-fetch-basics.html
index 99ccacdc784684b24267e6bcf12d6bdfed27d0fd..6bd8c5abf3f28b5b070d391173808c9c0898056f 100644
--- a/third_party/WebKit/LayoutTests/http/tests/serviceworker/foreign-fetch-basics.html
+++ b/third_party/WebKit/LayoutTests/http/tests/serviceworker/foreign-fetch-basics.html
@@ -236,6 +236,10 @@ promise_test(t => {
     return install_cross_origin_worker(t, worker_for_scopes(['']), scope)
       .then(() => fetch(remote_url, {method: 'SPECIAL'}))
       .then(response => response.text())
+      .then(response_text => assert_true(response_text.startsWith('report(')))
+      // Do the whole thing twice to test CORS preflight cache behavior.
+      .then(() => fetch(remote_url, {method: 'SPECIAL'}))
+      .then(response => response.text())
       .then(response_text => assert_true(response_text.startsWith('report(')));
   }, 'Service Worker does not intercept fetches with CORS preflight');