Make ResourceFetcher return Resources with LoadError instead of nullptrs.

third_party/WebKit/Source/core/fetch/ResourceFetcherTest.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 98 matching lines @@
   CachePolicy m_policy;
   std::unique_ptr<scheduler::FakeWebTaskRunner> m_runner;
   bool m_complete;
   long long m_transferSize;
 };
 
 class ResourceFetcherTest : public ::testing::Test {};
 
 TEST_F(ResourceFetcherTest, StartLoadAfterFrameDetach) {
   KURL secureURL(ParsedURLString, "https://secureorigin.test/image.png");
-  // Try to request a url. The request should fail, no resource should be
-  // returned, and no resource should be present in the cache.
+  // Try to request a url. The request should fail, and a resource in an error
+  // state should be returned, and no resource should be present in the cache.
   ResourceFetcher* fetcher = ResourceFetcher::create(nullptr);
   ResourceRequest resourceRequest(secureURL);
   resourceRequest.setRequestContext(WebURLRequest::RequestContextInternal);
   FetchRequest fetchRequest =
       FetchRequest(resourceRequest, FetchInitiatorInfo());
   Resource* resource = RawResource::fetch(fetchRequest, fetcher);
-  EXPECT_FALSE(resource);
+  ASSERT_TRUE(resource);
+  EXPECT_TRUE(resource->errorOccurred());
+  EXPECT_TRUE(resource->resourceError().isAccessCheck());
   EXPECT_FALSE(memoryCache()->resourceForURL(secureURL));
 
   // Start by calling startLoad() directly, rather than via requestResource().
   // This shouldn't crash.
   fetcher->startLoad(RawResource::create(secureURL, Resource::Raw));
 }
 
 TEST_F(ResourceFetcherTest, UseExistingResource) {
   ResourceFetcher* fetcher =
       ResourceFetcher::create(ResourceFetcherTestMockFetchContext::create());
@@ skipping 570 matching lines @@
   Platform::current()->getURLLoaderMockFactory()->registerURL(
       url, WebURLResponse(), "");
   Resource* newResource = RawResource::fetch(fetchRequest, fetcher);
   fetcher->stopFetching();
   Platform::current()->getURLLoaderMockFactory()->unregisterURL(url);
 
   EXPECT_NE(resource, newResource);
 }
 
 }  // namespace blink