Import //fetch from Web Platform Tests.

third_party/WebKit/LayoutTests/external/wpt/fetch/api/basic/request-forbidden-headers.js

+if (this.document === undefined) {
+  importScripts("/resources/testharness.js");
+  importScripts("../resources/utils.js");
+}
+
+function requestForbiddenHeaders(desc, forbiddenHeaders) {
+  var url = RESOURCES_DIR + "inspect-headers.py";
+  var requestInit = {"headers": forbiddenHeaders}
+  var urlParameters = "?headers=" + Object.keys(forbiddenHeaders).join("|");
+
+  promise_test(function(test){
+    return fetch(url + urlParameters, requestInit).then(function(resp) {
+      assert_equals(resp.status, 200, "HTTP status is 200");
+      assert_equals(resp.type , "basic", "Response's type is basic");
+      for (var header in forbiddenHeaders)
+        assert_not_equals(resp.headers.get("x-request-" + header), forbiddenHeaders[header], header + " does not have the value we defined");
+    });
+  }, desc);
+}
+
+requestForbiddenHeaders("Accept-Charset is a forbidden request header", {"Accept-Charset": "utf-8"});
+requestForbiddenHeaders("Accept-Encoding is a forbidden request header", {"Accept-Encoding": ""});
+
+requestForbiddenHeaders("Access-Control-Request-Headers is a forbidden request header", {"Access-Control-Request-Headers": ""});
+requestForbiddenHeaders("Access-Control-Request-Method is a forbidden request header", {"Access-Control-Request-Method": ""});
+requestForbiddenHeaders("Connection is a forbidden request header", {"Connection": "close"});
+requestForbiddenHeaders("Content-Length is a forbidden request header", {"Content-Length": "42"});
+requestForbiddenHeaders("Cookie is a forbidden request header", {"Cookie": "cookie=none"});
+requestForbiddenHeaders("Cookie2 is a forbidden request header", {"Cookie2": "cookie2=none"});
+requestForbiddenHeaders("Date is a forbidden request header", {"Date": "Wed, 04 May 1988 22:22:22 GMT"});
+requestForbiddenHeaders("DNT is a forbidden request header", {"DNT": "4"});
+requestForbiddenHeaders("Expect is a forbidden request header", {"Expect": "100-continue"});
+requestForbiddenHeaders("Host is a forbidden request header", {"Host": "http://wrong-host.com"});
+requestForbiddenHeaders("Keep-Alive is a forbidden request header", {"Keep-Alive": "timeout=15"});
+requestForbiddenHeaders("Origin is a forbidden request header", {"Origin": "http://wrong-origin.com"});
+requestForbiddenHeaders("Referer is a forbidden request header", {"Referer": "http://wrong-referer.com"});
+requestForbiddenHeaders("TE is a forbidden request header", {"TE": "trailers"});
+requestForbiddenHeaders("Trailer is a forbidden request header", {"Trailer": "Accept"});
+requestForbiddenHeaders("Transfer-Encoding is a forbidden request header", {"Transfer-Encoding": "chunked"});
+requestForbiddenHeaders("Upgrade is a forbidden request header", {"Upgrade": "HTTP/2.0"});
+requestForbiddenHeaders("Via is a forbidden request header", {"Via": "1.1 nowhere.com"});
+requestForbiddenHeaders("Proxy- is a forbidden request header", {"Proxy-": "value"});
+requestForbiddenHeaders("Proxy-Test is a forbidden request header", {"Proxy-Test": "value"});
+requestForbiddenHeaders("Sec- is a forbidden request header", {"Sec-": "value"});
+requestForbiddenHeaders("Sec-Test is a forbidden request header", {"Sec-Test": "value"});
+
+done();
+