Make img referrerpolicy attribute runtime-enabled

Source/core/loader/ImageLoader.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 27 matching lines @@
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/frame/UseCounter.h"
 #include "core/html/HTMLImageElement.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 #include "core/layout/LayoutImage.h"
 #include "core/layout/LayoutVideo.h"
 #include "core/layout/svg/LayoutSVGImage.h"
 #include "core/svg/graphics/SVGImage.h"
 #include "platform/Logging.h"
+#include "platform/RuntimeEnabledFeatures.h"
 #include "platform/weborigin/SecurityOrigin.h"
 #include "platform/weborigin/SecurityPolicy.h"
 #include "public/platform/WebURLRequest.h"
 
 namespace blink {
 
 static ImageEventSender& loadEventSender()
 {
     DEFINE_STATIC_LOCAL(ImageEventSender, sender, (EventTypeNames::load));
     return sender;
@@ skipping 253 matching lines @@
         // Unlike raw <img>, we block mixed content inside of <picture> or <img srcset>.
         ResourceLoaderOptions resourceLoaderOptions = ResourceFetcher::defaultResourceOptions();
         ResourceRequest resourceRequest(url);
         resourceRequest.setFetchCredentialsMode(WebURLRequest::FetchCredentialsModeSameOrigin);
         if (updateBehavior == UpdateForcedReload) {
             resourceRequest.setCachePolicy(ResourceRequestCachePolicy::ReloadBypassingCache);
             // ImageLoader defers the load of images when in an ImageDocument. Don't defer this load on a forced reload.
             m_loadingImageDocument = false;
         }
 
-        if (referrerPolicy != ReferrerPolicyDefault)
+        if (RuntimeEnabledFeatures::referrerPolicyAttributeEnabled() && referrerPolicy != ReferrerPolicyDefault)
             resourceRequest.setHTTPReferrer(SecurityPolicy::generateReferrer(referrerPolicy, url, document.outgoingReferrer()));
 
         if (isHTMLPictureElement(element()->parentNode()) || !element()->fastGetAttribute(HTMLNames::srcsetAttr).isNull())
             resourceRequest.setRequestContext(WebURLRequest::RequestContextImageSet);
         FetchRequest request(resourceRequest, element()->localName(), resourceLoaderOptions);
         configureRequest(request, bypassBehavior, *m_element, document.clientHintsPreferences());
 
         // Prevent the immediate creation of a ResourceLoader (and therefore a network
         // request) for ImageDocument loads. In this case, the image contents have already
         // been requested as a main resource and ImageDocumentParser will take care of
@@ skipping 341 matching lines @@
 
 void ImageLoader::sourceImageChanged()
 {
     for (auto& client : m_clients) {
         ImageLoaderClient* handle = client;
         handle->notifyImageSourceChanged();
     }
 }
 
 } // namespace blink