Remove calls to deprecated MessageLoop methods on Windows and Linux.

chrome/test/chromedriver/server/chromedriver_server.cc

Index: chrome/test/chromedriver/server/chromedriver_server.cc
diff --git a/chrome/test/chromedriver/server/chromedriver_server.cc b/chrome/test/chromedriver/server/chromedriver_server.cc
index 79d25fc4d70e150b6ba5c34f5d771d46b0da9b00..4abb1db5fa4ab2a55679037445f8894d486a15ed 100644
--- a/chrome/test/chromedriver/server/chromedriver_server.cc
+++ b/chrome/test/chromedriver/server/chromedriver_server.cc
@@ -208,7 +208,7 @@ void RunServer(uint16_t port,
   HttpRequestHandlerFunc handle_request_func =
       base::Bind(&HandleRequestOnCmdThread, &handler, whitelisted_ips);
 
-  io_thread.message_loop()->task_runner()->PostTask(
+  io_thread.task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&StartServerOnIOThread, port, allow_remote,
                  base::Bind(&HandleRequestOnIOThread, cmd_loop.task_runner(),
@@ -219,8 +219,8 @@ void RunServer(uint16_t port,
   // destroyed, which waits until all pending tasks have been completed.
   // This assumes the response is sent synchronously as part of the IO task.
   cmd_run_loop.Run();
-  io_thread.message_loop()->task_runner()->PostTask(
-      FROM_HERE, base::Bind(&StopServerOnIOThread));
+  io_thread.task_runner()->PostTask(FROM_HERE,
+                                    base::Bind(&StopServerOnIOThread));
 }
 
 }  // namespace