[wrapper-tracing] Untangle non-trivial mixin ctors

third_party/WebKit/Source/modules/fetch/FetchManager.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "modules/fetch/FetchManager.h"
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/V8ThrowException.h"
@@ skipping 392 matching lines @@
         LOG(FATAL) << "When ServiceWorker respond to the request from fetch() "
                       "with an error response, FetchManager::Loader::didFail() "
                       "must be called instead.";
         break;
     }
   }
 
   FetchResponseData* responseData = nullptr;
   SRIBytesConsumer* sriConsumer = nullptr;
   if (m_request->integrity().isEmpty()) {
-    responseData = FetchResponseData::createWithBuffer(new BodyStreamBuffer(
+    responseData = FetchResponseData::createWithBuffer(BodyStreamBuffer::create(
         scriptState,
         new BytesConsumerForDataConsumerHandle(
             scriptState->getExecutionContext(), std::move(handle))));
   } else {
     sriConsumer = new SRIBytesConsumer();
     responseData = FetchResponseData::createWithBuffer(
-        new BodyStreamBuffer(scriptState, sriConsumer));
+        BodyStreamBuffer::create(scriptState, sriConsumer));
   }
   responseData->setStatus(response.httpStatusCode());
   responseData->setStatusMessage(response.httpStatusText());
   for (auto& it : response.httpHeaderFields())
     responseData->headerList()->append(it.key, it.value);
   responseData->setURL(response.url());
   responseData->setMIMEType(response.mimeType());
   responseData->setResponseTime(response.responseTime());
 
   FetchResponseData* taintedResponse = nullptr;
@@ skipping 492 matching lines @@
   m_loaders.remove(loader);
   loader->dispose();
 }
 
 DEFINE_TRACE(FetchManager) {
   visitor->trace(m_loaders);
   ContextLifecycleObserver::trace(visitor);
 }
 
 }  // namespace blink