[Fetch, Loader] Expect on-heap objects will never get destroyed with a reference

third_party/WebKit/Source/core/loader/DocumentThreadableLoader.cpp

Index: third_party/WebKit/Source/core/loader/DocumentThreadableLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/DocumentThreadableLoader.cpp b/third_party/WebKit/Source/core/loader/DocumentThreadableLoader.cpp
index 74c57a434ad54417170b45faa936d222381da3fe..f7f1622aab03358c717827a354bdc4b488b71504 100644
--- a/third_party/WebKit/Source/core/loader/DocumentThreadableLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/DocumentThreadableLoader.cpp
@@ -647,7 +647,6 @@ bool DocumentThreadableLoader::redirectReceived(
   for (const auto& header : m_simpleRequestHeaders)
     crossOriginRequest.setHTTPHeaderField(header.key, header.value);
   makeCrossOriginAccessRequest(crossOriginRequest);
-  // |this| may be dead here.
 
   return false;
 }
@@ -963,14 +962,9 @@ void DocumentThreadableLoader::handlePreflightFailure(
 }
 
 void DocumentThreadableLoader::handleError(const ResourceError& error) {
-  // Copy the ResourceError instance to make it sure that the passed
-  // ResourceError is alive during didFail() even when the Resource is
-  // destructed during didFail().
-  ResourceError copiedError = error;
-
   ThreadableLoaderClient* client = m_client;
   clear();
-  client->didFail(copiedError);
+  client->didFail(error);
 }
 
 void DocumentThreadableLoader::loadRequestAsync(