Remove type mismatch condition in requestResource

third_party/WebKit/Source/platform/loader/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 561 matching lines @@
     case Revalidate:
       initializeRevalidation(resourceRequest, resource);
       break;
     case Use:
       if (resource->isLinkPreload() && !request.isLinkPreload())
         resource->setLinkPreload(false);
       break;
   }
   if (!resource)
     return nullptr;
-  if (resource->getType() != factory.type()) {
-    DCHECK(request.isSpeculativePreload() || request.isLinkPreload());
-    // TODO(yoav): What's the scenario where this can actually happen?
-    return nullptr;
-  }
+
+  // TODO(yoav): turn to a DCHECK. See https://crbug.com/690632
+  CHECK_EQ(resource->getType(), factory.type());
 
   if (!resource->isAlive())
     m_deadStatsRecorder.update(policy);
 
   if (policy != Use)
     resource->setIdentifier(identifier);
 
   // TODO(yoav): It is not clear why preloads are exempt from this check. Can we
   // remove the exemption?
   if (!request.isSpeculativePreload() || policy != Use) {
@@ skipping 223 matching lines @@
   RecordSriResourceIntegrityMismatchEvent(CheckingForIntegrityMismatch);
   if (existingResource->mustRefetchDueToIntegrityMetadata(fetchRequest)) {
     RecordSriResourceIntegrityMismatchEvent(RefetchDueToIntegrityMismatch);
     return Reload;
   }
 
   // Service Worker's CORS fallback message must not be cached.
   if (existingResource->response().wasFallbackRequiredByServiceWorker())
     return Reload;
 
-  // We already have a preload going for this URL.
-  if (fetchRequest.isSpeculativePreload() && existingResource->isPreloaded())
-    return Use;
-
   // If the same URL has been loaded as a different type, we need to reload.
   if (existingResource->getType() != type) {
     // FIXME: If existingResource is a Preload and the new type is LinkPrefetch
     // We really should discard the new prefetch since the preload has more
     // specific type information! crbug.com/379893
     // fast/dom/HTMLLinkElement/link-and-subresource-test hits this case.
     RESOURCE_LOADING_DVLOG(1) << "ResourceFetcher::determineRevalidationPolicy "
                                  "reloading due to type mismatch.";
     return Reload;
   }
 
+  // We already have a preload going for this URL.
+  if (fetchRequest.isSpeculativePreload() && existingResource->isPreloaded())
+    return Use;
+
   // Do not load from cache if images are not enabled. There are two general
   // cases:
   //
   // 1. Images are disabled. Don't ever load images, even if the image is cached
   // or it is a data: url. In this case, we "Reload" the image, then defer it
   // with resourceNeedsLoad() so that it never actually goes to the network.
   //
   // 2. Images are enabled, but not loaded automatically. In this case, we will
   // Use cached resources or data: urls, but will similarly fall back to a
   // deferred network load if we don't have the data available without a network
@@ skipping 688 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