[device] Replace MessageLoopProxy usage with ThreadTaskRunnerHandle

device/serial/serial_connection_factory.h

Index: device/serial/serial_connection_factory.h
diff --git a/device/serial/serial_connection_factory.h b/device/serial/serial_connection_factory.h
index befb209c0825532fb7f89778abf267a4ed661442..f1920ca797c877eefd18c1e6a70f46dfd16dd337 100644
--- a/device/serial/serial_connection_factory.h
+++ b/device/serial/serial_connection_factory.h
@@ -10,6 +10,8 @@
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "device/serial/data_stream.mojom.h"
 #include "device/serial/serial.mojom.h"
 #include "third_party/mojo/src/mojo/public/cpp/bindings/interface_request.h"
@@ -25,7 +27,7 @@ class SerialConnectionFactory
 
   SerialConnectionFactory(
       const IoHandlerFactory& io_handler_factory,
-      scoped_refptr<base::MessageLoopProxy> connect_message_loop);
+      scoped_refptr<base::SingleThreadTaskRunner> connect_message_loop);
 
   void CreateConnection(
       const std::string& path,
@@ -42,7 +44,7 @@ class SerialConnectionFactory
   virtual ~SerialConnectionFactory();
 
   const IoHandlerFactory io_handler_factory_;
-  scoped_refptr<base::MessageLoopProxy> connect_message_loop_;
+  scoped_refptr<base::SingleThreadTaskRunner> connect_message_loop_;
 
   DISALLOW_COPY_AND_ASSIGN(SerialConnectionFactory);
 };