Minor fixes in proxy configuration on iOS.

net/proxy/proxy_config_service_ios.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_config_service_ios.h"
 
 #include <CoreFoundation/CoreFoundation.h>
 #include <CFNetwork/CFProxySupport.h>
 
 #include "base/message_loop.h"
@@ skipping 79 matching lines @@
 
   // Proxy bypass boolean is not supported.
   // The kCFNetworkProxiesExcludeSimpleHostnames key is not available on iOS.
 
   // Source
   config->set_source(PROXY_CONFIG_SOURCE_SYSTEM);
 }
 
 }  // namespace
 
-ProxyConfigServiceIOS::ProxyConfigServiceIOS(
-    base::SingleThreadTaskRunner* io_thread_task_runner)
-    : PollingProxyConfigService(
-          base::TimeDelta::FromSeconds(kPollIntervalSec),
-          GetCurrentProxyConfig),
-      io_thread_task_runner_(io_thread_task_runner) {
-  DCHECK(io_thread_task_runner_);
+ProxyConfigServiceIOS::ProxyConfigServiceIOS()
+    : PollingProxyConfigService(base::TimeDelta::FromSeconds(kPollIntervalSec),
+                                GetCurrentProxyConfig) {
 }
 
 ProxyConfigServiceIOS::~ProxyConfigServiceIOS() {
-  DCHECK(io_thread_task_runner_->BelongsToCurrentThread());
 }
 
 }  // namespace net