Oilpan: Remove most WillBe types from the code base

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

 // 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.
 
 #ifndef FetchManager_h
 #define FetchManager_h
 
 #include "bindings/core/v8/ScriptPromise.h"
 #include "platform/heap/Handle.h"
 
@@ skipping 16 matching lines @@
 
     DECLARE_TRACE();
 
 private:
     class Loader;
 
     explicit FetchManager(ExecutionContext*);
     // Removes loader from |m_loaders|.
     void onLoaderFinished(Loader*);
 
-    RawPtrWillBeMember<ExecutionContext> m_executionContext;
+    Member<ExecutionContext> m_executionContext;
     HeapHashSet<Member<Loader>> m_loaders;
     bool m_isStopped;
 };
 
 } // namespace blink
 
 #endif // FetchManager_h