Minor fixes in proxy configuration on iOS.

net/proxy/proxy_config_service_ios.h

Index: net/proxy/proxy_config_service_ios.h
diff --git a/net/proxy/proxy_config_service_ios.h b/net/proxy/proxy_config_service_ios.h
index fff917a7f8c17ce54d03fa493b9fdef2a0405106..fd916188a4f4751d366f06749a0fca2eb03b0a01 100644
--- a/net/proxy/proxy_config_service_ios.h
+++ b/net/proxy/proxy_config_service_ios.h
@@ -16,16 +16,10 @@ namespace net {
 class ProxyConfigServiceIOS : public PollingProxyConfigService {
  public:
   // Constructs a ProxyConfigService that watches the iOS system proxy settings.
-  // This instance is expected to be operated and deleted on the IO thread
-  // (however it may be constructed from a different thread).
-  explicit ProxyConfigServiceIOS(
-      base::SingleThreadTaskRunner* io_thread_task_runner);
+  explicit ProxyConfigServiceIOS();
   virtual ~ProxyConfigServiceIOS();
 
  private:
-  // The thread that we expect to be operated on.
-  scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner_;
-
   DISALLOW_COPY_AND_ASSIGN(ProxyConfigServiceIOS);
 };