[wrapper-tracing] Untangle non-trivial mixin ctors

third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.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 BodyStreamBuffer_h
 #define BodyStreamBuffer_h
 
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptValue.h"
 #include "core/dom/DOMException.h"
@@ skipping 11 matching lines @@
 class ScriptState;
 
 class MODULES_EXPORT BodyStreamBuffer final : public UnderlyingSourceBase,
                                               public BytesConsumer::Client {
   WTF_MAKE_NONCOPYABLE(BodyStreamBuffer);
   USING_GARBAGE_COLLECTED_MIXIN(BodyStreamBuffer);
 
  public:
   // |consumer| must not have a client.
   // This function must be called with entering an appropriate V8 context.
-  BodyStreamBuffer(ScriptState*, BytesConsumer* /* consumer */);
+  static BodyStreamBuffer* create(ScriptState*, BytesConsumer* /* consumer */);
   // |ReadableStreamOperations::isReadableStream(stream)| must hold.
   // This function must be called with entering an appropriate V8 context.
-  BodyStreamBuffer(ScriptState*, ScriptValue stream);
+  static BodyStreamBuffer* create(ScriptState*, ScriptValue stream);
 
   ScriptValue stream();
 
   // Callable only when neither locked nor disturbed.
   PassRefPtr<BlobDataHandle> drainAsBlobDataHandle(
       BytesConsumer::BlobSizePolicy);
   PassRefPtr<EncodedFormData> drainAsFormData();
   void startLoading(FetchDataLoader*, FetchDataLoader::Client* /* client */);
   void tee(BodyStreamBuffer**, BodyStreamBuffer**);
 
@@ skipping 16 matching lines @@
 
   DEFINE_INLINE_TRACE() {
     visitor->trace(m_consumer);
     visitor->trace(m_loader);
     UnderlyingSourceBase::trace(visitor);
   }
 
  private:
   class LoaderClient;
 
+  BodyStreamBuffer(ScriptState*, BytesConsumer* /* consumer */);
+  BodyStreamBuffer(ScriptState*, ScriptValue stream);
+
+  void announceClientToConsumer();
+
   BytesConsumer* releaseHandle();
   void close();
   void error();
   void cancelConsumer();
   void processData();
   void endLoading();
   void stopLoading();
 
   RefPtr<ScriptState> m_scriptState;
   Member<BytesConsumer> m_consumer;
   // We need this member to keep it alive while loading.
   Member<FetchDataLoader> m_loader;
   bool m_streamNeedsMore = false;
   bool m_madeFromReadableStream;
 };
 
 }  // namespace blink
 
 #endif  // BodyStreamBuffer_h