Revert of Revert of Never send a referrer header if the referrer is not a web url

Source/platform/weborigin/SecurityPolicy.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 52 matching lines @@
     bool URLIsSecureURL = url.protocolIs("https");
 
     return !URLIsSecureURL;
 }
 
 String SecurityPolicy::generateReferrerHeader(ReferrerPolicy referrerPolicy, const KURL& url, const String& referrer)
 {
     if (referrer.isEmpty())
         return String();
 
+    if (!(protocolIs(referrer, "https") || protocolIs(referrer, "http")))
+        return String();
+
     switch (referrerPolicy) {
     case ReferrerPolicyNever:
         return String();
     case ReferrerPolicyAlways:
         return referrer;
     case ReferrerPolicyOrigin: {
         String origin = SecurityOrigin::createFromString(referrer)->toString();
         if (origin == "null")
             return String();
         // A security origin is not a canonical URL as it lacks a path. Add /
@@ skipping 64 matching lines @@
         map.remove(it);
 }
 
 void SecurityPolicy::resetOriginAccessWhitelists()
 {
     ASSERT(isMainThread());
     originAccessMap().clear();
 }
 
 } // namespace WebCore