Introduce NavigationSimulator to use in unit tests

content/public/common/referrer.h

Index: content/public/common/referrer.h
diff --git a/content/public/common/referrer.h b/content/public/common/referrer.h
index 75ae4b37d9839cb500cf4a1364dab08d40f657a4..68c35f44d993e56e04763ec989f23ee06df9c4e9 100644
--- a/content/public/common/referrer.h
+++ b/content/public/common/referrer.h
@@ -7,13 +7,10 @@
 
 #include "base/logging.h"
 #include "content/common/content_export.h"
+#include "net/url_request/url_request.h"
 #include "third_party/WebKit/public/platform/WebReferrerPolicy.h"
 #include "url/gurl.h"
 
-namespace net {
-class URLRequest;
-}
-
 namespace content {
 
 // This struct holds a referrer URL, as well as the referrer policy to be
@@ -32,6 +29,9 @@ struct CONTENT_EXPORT Referrer {
 
   static void SetReferrerForRequest(net::URLRequest* request,
                                     const Referrer& referrer);
+
+  static net::URLRequest::ReferrerPolicy ReferrerPolicyForUrlRequest(
+      const Referrer& referrer);
 };
 
 }  // namespace content