Don't set referrers on outgoing plugin requests if the load_manually flag is ...

chrome/test/ui/npapi_uitest.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // windows headers
 #include <windows.h>
 #include <shellapi.h>
 #include <shlobj.h>
 #include <comutil.h>
 
@@ skipping 389 matching lines @@
 // exception.  Should be run for in and out of process plugins, but
 // the more interesting case is out of process, where we must route
 // the exception to the correct renderer.
 TEST_F(NPAPITester, NPObjectSetException) {
   GURL url = GetTestUrl(L"npapi", L"npobject_set_exception.html");
   NavigateToURL(url);
   WaitForFinish("npobject_set_exception", "1", url,
                 kTestCompleteCookie, kTestCompleteSuccess,
                 kShortWaitTimeout);
 }
+
+TEST_F(NPAPIVisiblePluginTester, PluginReferrerTest) {
+  if (UITest::in_process_renderer())
+    return;
+
+  GURL url(URLRequestMockHTTPJob::GetMockUrl(
+               FilePath(FILE_PATH_LITERAL(
+                            "npapi/plugin_url_request_referrer_test.html"))));
+
+  NavigateToURL(url);
+
+  WaitForFinish("plugin_referrer_test", "1", url, kTestCompleteCookie,
+                kTestCompleteSuccess, kShortWaitTimeout);
+}
+