Make ResourceFetcher return Resources with LoadError instead of nullptrs.

third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
     Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
     Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All
     rights reserved.
     Copyright (C) 2009 Torch Mobile Inc. http://www.torchmobile.com/
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
@@ skipping 414 matching lines @@
   resource->setIdentifier(createUniqueIdentifier());
   resource->setCacheIdentifier(cacheIdentifier);
   resource->finish();
 
   if (!substituteData.isValid())
     memoryCache()->add(resource);
 
   return resource;
 }
 
+Resource* ResourceFetcher::resourceForBlockedRequest(
+    const FetchRequest& request,
+    const ResourceFactory& factory) {
+  Resource* resource = factory.create(request.resourceRequest(),
+                                      request.options(), request.charset());
+  resource->error(ResourceError::cancelledDueToAccessCheckError(request.url()));
+  return resource;
+}
+
 void ResourceFetcher::moveCachedNonBlockingResourceToBlocking(
     Resource* resource,
     const FetchRequest& request) {
   // TODO(yoav): Test that non-blocking resources (video/audio/track) continue
   // to not-block even after being preloaded and discovered.
   if (resource && resource->loader() &&
       resource->isLoadEventBlockingResourceType() &&
       resource->isLinkPreload() && !request.forPreload()) {
     m_nonBlockingLoaders.remove(resource->loader());
     m_loaders.add(resource->loader());
@@ skipping 43 matching lines @@
   TRACE_EVENT1("blink", "ResourceFetcher::requestResource", "url",
                urlForTraceEvent(request.url()));
 
   if (!request.url().isValid())
     return nullptr;
 
   if (!context().canRequest(
           factory.type(), request.resourceRequest(),
           MemoryCache::removeFragmentIdentifierIfNeeded(request.url()),
           request.options(), request.forPreload(),
-          request.getOriginRestriction()))
-    return nullptr;
+          request.getOriginRestriction())) {
+    DCHECK(!substituteData.forceSynchronousLoad());
+    return resourceForBlockedRequest(request, factory);
+  }
 
   unsigned long identifier = createUniqueIdentifier();
   request.mutableResourceRequest().setPriority(computeLoadPriority(
       factory.type(), request, ResourcePriority::NotVisible));
   initializeResourceRequest(request.mutableResourceRequest(), factory.type(),
                             request.defer());
   context().willStartLoadingResource(
       identifier, request.mutableResourceRequest(), factory.type());
   if (!request.url().isValid())
     return nullptr;
@@ skipping 1083 matching lines @@
   visitor->trace(m_context);
   visitor->trace(m_archive);
   visitor->trace(m_loaders);
   visitor->trace(m_nonBlockingLoaders);
   visitor->trace(m_documentResources);
   visitor->trace(m_preloads);
   visitor->trace(m_resourceTimingInfoMap);
 }
 
 }  // namespace blink