Remove the dependence on BrowserThread::FILE for

net/proxy/proxy_service.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 "net/proxy/proxy_service.h"
 
 #include <algorithm>
 #include <cmath>
 #include <utility>
 
@@ skipping 1505 matching lines @@
 
 void ProxyService::ForceReloadProxyConfig() {
   DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
   ResetProxyConfig(false);
   ApplyProxyConfigIfAvailable();
 }
 
 // static
 std::unique_ptr<ProxyConfigService>
 ProxyService::CreateSystemProxyConfigService(
-    const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
-    const scoped_refptr<base::SingleThreadTaskRunner>& file_task_runner) {
+    const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner) {
 #if defined(OS_WIN)
   return base::MakeUnique<ProxyConfigServiceWin>();
 #elif defined(OS_IOS)
   return base::MakeUnique<ProxyConfigServiceIOS>();
 #elif defined(OS_MACOSX)
   return base::MakeUnique<ProxyConfigServiceMac>(io_task_runner);
 #elif defined(OS_CHROMEOS)
   LOG(ERROR) << "ProxyConfigService for ChromeOS should be created in "
              << "profile_io_data.cc::CreateProxyConfigService and this should "
              << "be used only for examples.";
   return base::WrapUnique(new UnsetProxyConfigService);
 #elif defined(OS_LINUX)
   std::unique_ptr<ProxyConfigServiceLinux> linux_config_service(
       new ProxyConfigServiceLinux());
 
   // Assume we got called on the thread that runs the default glib
   // main loop, so the current thread is where we should be running
   // gconf calls from.
   scoped_refptr<base::SingleThreadTaskRunner> glib_thread_task_runner =
       base::ThreadTaskRunnerHandle::Get();
 
   // Synchronously fetch the current proxy config (since we are running on
   // glib_default_loop). Additionally register for notifications (delivered in
-  // either |glib_default_loop| or |file_task_runner|) to keep us updated when
-  // the proxy config changes.
-  linux_config_service->SetupAndFetchInitialConfig(
-      glib_thread_task_runner, io_task_runner, file_task_runner);
+  // either |glib_default_loop| or an internal sequenced task runner) to
+  // keep us updated when the proxy config changes.
+  linux_config_service->SetupAndFetchInitialConfig(glib_thread_task_runner,
+                                                   io_task_runner);
 
   return std::move(linux_config_service);
 #elif defined(OS_ANDROID)
   return base::MakeUnique<ProxyConfigServiceAndroid>(
       io_task_runner, base::ThreadTaskRunnerHandle::Get());
 #else
   LOG(WARNING) << "Failed to choose a system proxy settings fetcher "
                   "for this platform.";
   return base::MakeUnique<ProxyConfigServiceDirect>();
 #endif
@@ skipping 107 matching lines @@
   State previous_state = ResetProxyConfig(false);
   if (previous_state != STATE_NONE)
     ApplyProxyConfigIfAvailable();
 }
 
 void ProxyService::OnDNSChanged() {
   OnIPAddressChanged();
 }
 
 }  // namespace net