Add new system url request context getter to the blimp engine.

blimp/engine/app/blimp_system_url_request_context_getter.h

+// Copyright 2016 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 BLIMP_ENGINE_APP_BLIMP_SYSTEM_URL_REQUEST_CONTEXT_GETTER_H_
+#define BLIMP_ENGINE_APP_BLIMP_SYSTEM_URL_REQUEST_CONTEXT_GETTER_H_
+
+#include "base/files/file_path.h"
+#include "base/macros.h"
+#include "content/public/browser/content_browser_client.h"
+#include "net/url_request/url_request_context_getter.h"
+
+namespace base {
+class MessageLoop;
+class SingleThreadTaskRunner;
+}
+
+namespace blimp {
+namespace engine {
+
+// The URLRequestContextGetter for Blimp system requests that should not be
+// associated with a user URL request context (e.g. metrics upload).
+class BlimpSystemURLRequestContextGetter : public net::URLRequestContextGetter {
+ public:
+  BlimpSystemURLRequestContextGetter();
+
+  // net::URLRequestContextGetter implementation.
+  net::URLRequestContext* GetURLRequestContext() override;
+  scoped_refptr<base::SingleThreadTaskRunner> GetNetworkTaskRunner()
+      const override;
+
+ private:
+  ~BlimpSystemURLRequestContextGetter() override;
+
+  std::unique_ptr<net::URLRequestContext> url_request_context_;
+
+  DISALLOW_COPY_AND_ASSIGN(BlimpSystemURLRequestContextGetter);
+};
+
+}  // namespace engine
+}  // namespace blimp
+
+#endif  // BLIMP_ENGINE_APP_BLIMP_SYSTEM_URL_REQUEST_CONTEXT_GETTER_H_