Remove ResourceFetcher's access to a real FetchContext at frame detach time

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 33 matching lines @@
 namespace blink {
 
 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.
-    RefPtrWillBeRawPtr<ResourceFetcher> fetcher = ResourceFetcher::create(FetchContext::create());
+    RefPtrWillBeRawPtr<ResourceFetcher> fetcher = ResourceFetcher::create(nullptr);
     FetchRequest fetchRequest = FetchRequest(ResourceRequest(secureURL), FetchInitiatorInfo());
     ResourcePtr<ImageResource> image = fetcher->fetchImage(fetchRequest);
     EXPECT_EQ(image.get(), static_cast<ImageResource*>(0));
     EXPECT_EQ(memoryCache()->resourceForURL(secureURL), static_cast<Resource*>(0));
 }
 
 } // namespace blink