Fix link header preload on subresources

third_party/WebKit/Source/core/loader/FrameFetchContext.cpp

 /*
  * Copyright (C) 2013 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 233 matching lines @@
 {
     frame()->loader().applyUserAgent(request);
     frame()->loader().client()->dispatchWillSendRequest(m_documentLoader, identifier, request, redirectResponse);
     TRACE_EVENT_INSTANT1("devtools.timeline", "ResourceSendRequest", TRACE_EVENT_SCOPE_THREAD, "data", InspectorSendRequestEvent::data(identifier, frame(), request));
     InspectorInstrumentation::willSendRequest(frame(), identifier, ensureLoaderForNotifications(), request, redirectResponse, initiatorInfo);
 }
 
 void FrameFetchContext::dispatchDidReceiveResponse(unsigned long identifier, const ResourceResponse& response, ResourceLoader* resourceLoader)
 {
     MixedContentChecker::checkMixedPrivatePublic(frame(), response.remoteIPAddress());
-    LinkLoader::loadLinkFromHeader(response.httpHeaderField(HTTPNames::Link), frame()->document(), NetworkHintsInterfaceImpl(), LinkLoader::DoNotLoadResources);

[Nate Chapin, 2016/01/25 21:50:10]

Maybe keep the loadLinkFromHeader() call here, and just vary the
DoNotLoadResources/LoadResourcesAndPreconnect, with a comment explaining why.

[Yoav Weiss, 2016/01/25 22:12:45]

Yeah. Certainly DRYer to have a single call. I'll move it after the condition,
so we won't have to branch twice.

     if (m_documentLoader == frame()->loader().provisionalDocumentLoader()) {
+        LinkLoader::loadLinkFromHeader(response.httpHeaderField(HTTPNames::Link), frame()->document(), NetworkHintsInterfaceImpl(), LinkLoader::DoNotLoadResources);
         ResourceFetcher* fetcher = nullptr;
         if (frame()->document())
             fetcher = frame()->document()->fetcher();
         m_documentLoader->clientHintsPreferences().updateFromAcceptClientHintsHeader(response.httpHeaderField(HTTPNames::Accept_CH), fetcher);
+    } else {
+        LinkLoader::loadLinkFromHeader(response.httpHeaderField(HTTPNames::Link), frame()->document(), NetworkHintsInterfaceImpl(), LinkLoader::LoadResourcesAndPreconnect);
     }
 
     if (response.hasMajorCertificateErrors() && resourceLoader)
         MixedContentChecker::handleCertificateError(frame(), resourceLoader->originalRequest(), response);
 
     frame()->loader().progress().incrementProgress(identifier, response);
     frame()->loader().client()->dispatchDidReceiveResponse(m_documentLoader, identifier, response);
     TRACE_EVENT_INSTANT1("devtools.timeline", "ResourceReceiveResponse", TRACE_EVENT_SCOPE_THREAD, "data", InspectorReceiveResponseEvent::data(identifier, frame(), response));
     DocumentLoader* documentLoader = ensureLoaderForNotifications();
     InspectorInstrumentation::didReceiveResourceResponse(frame(), identifier, documentLoader, response, resourceLoader);
@@ skipping 513 matching lines @@
 }
 
 DEFINE_TRACE(FrameFetchContext)
 {
     visitor->trace(m_document);
     visitor->trace(m_documentLoader);
     FetchContext::trace(visitor);
 }
 
 } // namespace blink