Create a TrivialURLRequestContextGetter to shim an existing URLRequestContext.

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/memory/ref_counted.h"
 #include "base/sequenced_task_runner_helpers.h"
 #include "net/base/net_export.h"
@@ skipping 35 matching lines @@
   // IO happens.
   void OnDestruct() const;
 };
 
 struct URLRequestContextGetterTraits {
   static void Destruct(const URLRequestContextGetter* context_getter) {
     context_getter->OnDestruct();
   }
 };
 
+// For use in shimming a URLRequestContext into a URLRequestContextGetter.
+class NET_EXPORT TrivialURLRequestContextGetter
+    : public URLRequestContextGetter {
+public:
+  TrivialURLRequestContextGetter(
+      net::URLRequestContext* context,
+      const scoped_refptr<base::SingleThreadTaskRunner>& main_task_runner);
+
+  // net::URLRequestContextGetter implementation:
+  virtual net::URLRequestContext* GetURLRequestContext() OVERRIDE;
+
+  virtual scoped_refptr<base::SingleThreadTaskRunner>
+      GetNetworkTaskRunner() const OVERRIDE;
+
+private:
+  virtual ~TrivialURLRequestContextGetter();
+
+  net::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_