Loader: Remove ResourceType::kPrefetch param from the ctor of LinkFetchResource

For code cleanup, this CL removes the resource type param from the ctor
of LinkFetchResource that was always ResourceType::kPrefetch, and
instead hard-codes the resource type in the class.

Bug: 1075582
Change-Id: I2230f107968969c6df71bacd8089d1a82b1dd0fb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2210338Reviewed-by: Yutaka Hirano <yhirano@chromium.org>
Commit-Queue: Hiroki Nakagawa <nhiroki@chromium.org>
Cr-Commit-Position: refs/heads/master@{#770943}

third_party/blink/renderer/core/loader/preload_helper.cc

@@ -551,8 +551,7 @@ Resource* PreloadHelper::PrefetchIfNeeded(const LinkLoadParameters& params,
             SignedExchangePrefetchCacheForNavigationsEnabled() ||
         RuntimeEnabledFeatures::SignedExchangeSubresourcePrefetchEnabled(
             &document));
-    return LinkFetchResource::Fetch(ResourceType::kLinkPrefetch,
-                                    link_fetch_params, document.Fetcher());
+    return LinkFetchResource::Fetch(link_fetch_params, document.Fetcher());
   }
   return nullptr;
 }

third_party/blink/renderer/core/loader/resource/link_fetch_resource.cc

@@ -10,18 +10,24 @@
 
 namespace blink {
 
-Resource* LinkFetchResource::Fetch(ResourceType type,
-                                   FetchParameters& params,
+Resource* LinkFetchResource::Fetch(FetchParameters& params,
                                    ResourceFetcher* fetcher) {
-  DCHECK_EQ(type, ResourceType::kLinkPrefetch);
-  return fetcher->RequestResource(params, LinkResourceFactory(type), nullptr);
+  return fetcher->RequestResource(params, LinkResourceFactory(), nullptr);
 }
 
 LinkFetchResource::LinkFetchResource(const ResourceRequest& request,
-                                     ResourceType type,
                                      const ResourceLoaderOptions& options)
-    : Resource(request, type, options) {}
+    : Resource(request, ResourceType::kLinkPrefetch, options) {}
 
 LinkFetchResource::~LinkFetchResource() = default;
 
+LinkFetchResource::LinkResourceFactory::LinkResourceFactory()
+    : NonTextResourceFactory(ResourceType::kLinkPrefetch) {}
+
+Resource* LinkFetchResource::LinkResourceFactory::Create(
+    const ResourceRequest& request,
+    const ResourceLoaderOptions& options) const {
+  return MakeGarbageCollected<LinkFetchResource>(request, options);
+}
+
 }  // namespace blink

third_party/blink/renderer/core/loader/resource/link_fetch_resource.h

@@ -6,33 +6,29 @@
 #define THIRD_PARTY_BLINK_RENDERER_CORE_LOADER_RESOURCE_LINK_FETCH_RESOURCE_H_
 
 #include "third_party/blink/renderer/platform/loader/fetch/resource.h"
-#include "third_party/blink/renderer/platform/loader/fetch/resource_client.h"
 
 namespace blink {
 
 class FetchParameters;
 class ResourceFetcher;
 
+// This is the implementation of Resource for <link rel='prefetch'>.
+// TODO(nhiroki): Rename this to LinkPrefetchResource.
 class LinkFetchResource final : public Resource {
  public:
-  static Resource* Fetch(ResourceType, FetchParameters&, ResourceFetcher*);
+  static Resource* Fetch(FetchParameters&, ResourceFetcher*);
 
   LinkFetchResource(const ResourceRequest&,
-                    ResourceType,
                     const ResourceLoaderOptions&);
   ~LinkFetchResource() override;
 
  private:
-  class LinkResourceFactory : public NonTextResourceFactory {
+  class LinkResourceFactory final : public NonTextResourceFactory {
    public:
-    explicit LinkResourceFactory(ResourceType type)
-        : NonTextResourceFactory(type) {}
+    LinkResourceFactory();
 
     Resource* Create(const ResourceRequest& request,
-                     const ResourceLoaderOptions& options) const override {
-      return MakeGarbageCollected<LinkFetchResource>(request, GetType(),
-                                                     options);
-    }
+                     const ResourceLoaderOptions& options) const override;
   };
 };