Print creator's call-stack on URLRequestContextGetter leak in Debug.

net/url_request/url_request_context_getter.h

 // Copyright (c) 2012 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 NET_URL_REQUEST_URL_REQUEST_CONTEXT_GETTER_H_
 #define NET_URL_REQUEST_URL_REQUEST_CONTEXT_GETTER_H_
 
+#include "base/debug/stack_trace.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/observer_list.h"
 #include "base/sequenced_task_runner_helpers.h"
 #include "net/base/net_export.h"
 
 namespace base {
 class SingleThreadTaskRunner;
 }  // namespace base
 
@@ skipping 45 matching lines @@
   // against reentrancy.
   void NotifyContextShuttingDown();
 
  private:
   // OnDestruct is used to ensure deletion on the thread on which the request
   // IO happens.
   void OnDestruct() const;
 
   base::ObserverList<URLRequestContextGetterObserver> observer_list_;
 
+#if !defined(NDEBUG)
+  base::debug::StackTrace created_at;
+#endif  // !defined(NDEBUG)
+
   DISALLOW_COPY_AND_ASSIGN(URLRequestContextGetter);
 };
 
 struct URLRequestContextGetterTraits {
   static void Destruct(const URLRequestContextGetter* context_getter) {
     context_getter->OnDestruct();
   }
 };
 
 // For use in shimming a URLRequestContext into a URLRequestContextGetter.
@@ skipping 15 matching lines @@
 
   URLRequestContext* context_;
   const scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(TrivialURLRequestContextGetter);
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_CONTEXT_GETTER_H_