Oilpan: Remove most WillBe types from the code base

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 36 matching lines @@
 namespace {
 
 bool IsRedirectStatusCode(int statusCode)
 {
     return (statusCode == 301 || statusCode == 302 || statusCode == 303 || statusCode == 307 || statusCode == 308);
 }
 
 } // namespace
 
 class FetchManager::Loader final : public GarbageCollectedFinalized<FetchManager::Loader>, public ThreadableLoaderClient, public ContextLifecycleObserver {
-    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(FetchManager::Loader);
+    USING_GARBAGE_COLLECTED_MIXIN(FetchManager::Loader);
 public:
     static Loader* create(ExecutionContext* executionContext, FetchManager* fetchManager, ScriptPromiseResolver* resolver, FetchRequestData* request, bool isIsolatedWorld)
     {
         return new Loader(executionContext, fetchManager, resolver, request, isIsolatedWorld);
     }
 
     ~Loader() override;
     DECLARE_VIRTUAL_TRACE();
 
     void didReceiveResponse(unsigned long, const ResourceResponse&, PassOwnPtr<WebDataConsumerHandle>) override;
@@ skipping 646 matching lines @@
     loader->dispose();
 }
 
 DEFINE_TRACE(FetchManager)
 {
     visitor->trace(m_executionContext);
     visitor->trace(m_loaders);
 }
 
 } // namespace blink