[Dial] Refactor DialRegistry and DeviceDescriptionFetcher so they can be used by MediaSinkService

chrome/browser/extensions/api/dial/dial_api.cc

 // 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.
 
 #include "chrome/browser/extensions/api/dial/dial_api.h"
 
 #include <stddef.h>
 #include <utility>
 #include <vector>
 
@@ skipping 212 matching lines @@
     return;
   }
 
   if (dial_->test_device_data_ && dial_->test_device_description_ &&
       dial_->test_device_data_->device_description_url() == url) {
     OnFetchComplete(*(dial_->test_device_description_));
     return;
   }
 
   device_description_fetcher_ = base::MakeUnique<DeviceDescriptionFetcher>(
-      url, Profile::FromBrowserContext(browser_context()),
+      url, Profile::FromBrowserContext(browser_context())->GetRequestContext(),
+      BrowserThread::UI,
       base::BindOnce(&DialFetchDeviceDescriptionFunction::OnFetchComplete,
                      this),
       base::BindOnce(&DialFetchDeviceDescriptionFunction::OnFetchError, this));
 
   device_description_fetcher_->Start();
 }
 
 void DialFetchDeviceDescriptionFunction::OnFetchComplete(
     const api::dial::DialDeviceDescriptionData& result) {
   // Destroy the DeviceDescriptionFetcher since it still contains a reference
@@ skipping 10 matching lines @@
 void DialFetchDeviceDescriptionFunction::OnFetchError(
     const std::string& message) {
   // Destroy the DeviceDescriptionFetcher since it still contains a reference
   // to |this| in its un-invoked callback.
   device_description_fetcher_.reset();
   SetError(message);
   SendResponse(false);
 }
 
 }  // namespace extensions