Add use counter for preload link headers

third_party/WebKit/Source/core/loader/LinkLoader.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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 198 matching lines @@
     case Resource::TextTrack:
         break;
     case Resource::Raw:
     case Resource::LinkSubresource:
         break;
     default:
         ASSERT_NOT_REACHED();
     }
 }
 
-static ResourcePtr<Resource> preloadIfNeeded(const LinkRelAttribute& relAttribute, const KURL& href, Document& document, const String& as)
+static ResourcePtr<Resource> preloadIfNeeded(const LinkRelAttribute& relAttribute, const KURL& href, Document& document, const String& as, LinkCaller caller)
 {
     if (!document.loader() || !relAttribute.isLinkPreload())
         return nullptr;
 
     UseCounter::count(document, UseCounter::LinkRelPreload);
     ASSERT(RuntimeEnabledFeatures::linkPreloadEnabled());
     if (!href.isValid() || href.isEmpty()) {
         document.addConsoleMessage(ConsoleMessage::create(OtherMessageSource, WarningMessageLevel, String("<link rel=preload> has an invalid `href` value")));
         return nullptr;
     }
+    if (caller == LinkCalledFromHeader)
+        UseCounter::count(document, UseCounter::LinkHeaderPreload);
     Resource::Type type = LinkLoader::getTypeFromAsAttribute(as, &document);
     ResourceRequest resourceRequest(document.completeURL(href));
     ResourceFetcher::determineRequestContext(resourceRequest, type, false);
     FetchRequest linkRequest(resourceRequest, FetchInitiatorTypeNames::link);
 
     linkRequest.setPriority(document.fetcher()->loadPriority(type, linkRequest));
     Settings* settings = document.settings();
     if (settings && settings->logPreload())
         document.addConsoleMessage(ConsoleMessage::create(OtherMessageSource, DebugMessageLevel, String("Preload triggered for " + href.host() + href.path())));
     linkRequest.setForPreload(true);
@@ skipping 13 matching lines @@
         LinkRelAttribute relAttribute(header.rel());
         KURL url = document->completeURL(header.url());
         if (canLoadResources == DoNotLoadResources) {
             if (RuntimeEnabledFeatures::linkHeaderEnabled())
                 dnsPrefetchIfNeeded(relAttribute, url, *document, networkHintsInterface, LinkCalledFromHeader);
 
             if (RuntimeEnabledFeatures::linkPreconnectEnabled())
                 preconnectIfNeeded(relAttribute, url, *document, header.crossOrigin(), networkHintsInterface, LinkCalledFromHeader);
         } else {
             if (RuntimeEnabledFeatures::linkPreloadEnabled())
-                preloadIfNeeded(relAttribute, url, *document, header.as());
+                preloadIfNeeded(relAttribute, url, *document, header.as(), LinkCalledFromHeader);
         }
         // TODO(yoav): Add more supported headers as needed.
     }
     return true;
 }
 
 bool LinkLoader::loadLink(const LinkRelAttribute& relAttribute, CrossOriginAttributeValue crossOrigin, const String& type, const String& as, const KURL& href, Document& document, const NetworkHintsInterface& networkHintsInterface)
 {
     // TODO(yoav): Do all links need to load only after they're in document???
 
     // TODO(yoav): Convert all uses of the CrossOriginAttribute to CrossOriginAttributeValue. crbug.com/486689
     // FIXME(crbug.com/463266): We're ignoring type here. Maybe we shouldn't.
     dnsPrefetchIfNeeded(relAttribute, href, document, networkHintsInterface, LinkCalledFromMarkup);
 
     preconnectIfNeeded(relAttribute, href, document, crossOrigin, networkHintsInterface, LinkCalledFromMarkup);
 
     if (m_client->shouldLoadLink())
-        createLinkPreloadResourceClient(preloadIfNeeded(relAttribute, href, document, as));
+        createLinkPreloadResourceClient(preloadIfNeeded(relAttribute, href, document, as, LinkCalledFromMarkup));
 
     // FIXME(crbug.com/323096): Should take care of import.
     if ((relAttribute.isLinkPrefetch() || relAttribute.isLinkSubresource()) && href.isValid() && document.frame()) {
         if (!m_client->shouldLoadLink())
             return false;
         Resource::Type type = Resource::LinkPrefetch;
         if (relAttribute.isLinkSubresource()) {
             type = Resource::LinkSubresource;
             UseCounter::count(document, UseCounter::LinkRelSubresource);
         } else {
@@ skipping 33 matching lines @@
 
 DEFINE_TRACE(LinkLoader)
 {
     visitor->trace(m_client);
     visitor->trace(m_prerender);
     visitor->trace(m_linkPreloadResourceClient);
     ResourceOwner<Resource, ResourceClient>::trace(visitor);
 }
 
 }