Make ResourceFetcher return Resources with LoadError instead of nullptrs.

third_party/WebKit/Source/web/tests/WebFrameTest.cpp

 /*
  * Copyright (C) 2010 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 6874 matching lines @@
 {
     URLTestHelpers::registerMockedURLLoad(toKURL(m_notBaseURL + "link-manifest-fetch.json"), "link-manifest-fetch.json");
     registerMockedHttpURLLoadWithCSP("foo.html", "manifest-src 'self'");
 
     FrameTestHelpers::WebViewHelper webViewHelper;
     webViewHelper.initializeAndLoad(m_baseURL + "foo.html");
     Document* document = webViewHelper.webView()->mainFrameImpl()->frame()->document();
 
     Resource* resource = fetchManifest(document, toKURL(m_notBaseURL + "link-manifest-fetch.json"));
 
-    EXPECT_EQ(0, resource); // Fetching resource wasn't allowed.
+    // Fetching resource wasn't allowed.
+    ASSERT_TRUE(resource);
+    EXPECT_TRUE(resource->errorOccurred());
+    EXPECT_TRUE(resource->resourceError().isAccessCheck());
 }
 
 TEST_P(ParameterizedWebFrameTest, ManifestCSPFetchSelfReportOnly)
 {
     URLTestHelpers::registerMockedURLLoad(toKURL(m_notBaseURL + "link-manifest-fetch.json"), "link-manifest-fetch.json");
     registerMockedHttpURLLoadWithCSP("foo.html", "manifest-src 'self'", /* report only */ true);
 
     FrameTestHelpers::WebViewHelper webViewHelper;
     webViewHelper.initializeAndLoad(m_baseURL + "foo.html");
     Document* document = webViewHelper.webView()->mainFrameImpl()->frame()->document();
@@ skipping 2032 matching lines @@
     FrameTestHelpers::WebViewHelper helper;
     helper.initializeAndLoad(url, true);
     Platform::current()->getURLLoaderMockFactory()->setLoaderDelegate(nullptr);
 
     Document* document = toLocalFrame(helper.webView()->page()->mainFrame())->document();
     EXPECT_TRUE(document->isImageDocument());
     EXPECT_EQ(Resource::DecodeError, toImageDocument(document)->cachedImage()->getStatus());
 }
 
 } // namespace blink