Revert of [inspector] use creation stack trace as parent for async call chains

src/inspector/v8-stack-trace-impl.h

 // Copyright 2016 the V8 project 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 V8_INSPECTOR_V8STACKTRACEIMPL_H_
 #define V8_INSPECTOR_V8STACKTRACEIMPL_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 84 matching lines @@
 
   std::unique_ptr<protocol::Runtime::StackTrace> buildInspectorObject(
       AsyncStackTrace* asyncCreation, int maxAsyncDepth) const;
 
   int contextGroupId() const;
   const String16& description() const;
   std::weak_ptr<AsyncStackTrace> parent() const;
   std::weak_ptr<AsyncStackTrace> creation() const;
   bool isEmpty() const;
 
-  void setDescription(const String16& description) {
-    // TODO(kozyatinskiy): implement it without hack.
-    DCHECK(!m_description.length() || m_description == description);
-    m_description = description;
-  }
-
  private:
   AsyncStackTrace(int contextGroupId, const String16& description,
                   std::vector<std::shared_ptr<StackFrame>> frames,
                   std::shared_ptr<AsyncStackTrace> asyncParent,
                   std::shared_ptr<AsyncStackTrace> asyncCreation);
 
   int m_contextGroupId;
   String16 m_description;
 
   std::vector<std::shared_ptr<StackFrame>> m_frames;
   std::weak_ptr<AsyncStackTrace> m_asyncParent;
   std::weak_ptr<AsyncStackTrace> m_asyncCreation;
 
   DISALLOW_COPY_AND_ASSIGN(AsyncStackTrace);
 };
 
 }  // namespace v8_inspector
 
 #endif  // V8_INSPECTOR_V8STACKTRACEIMPL_H_