Remove calls to deprecated MessageLoop methods on Windows and Linux.

ui/shell_dialogs/select_file_dialog_win.cc

Index: ui/shell_dialogs/select_file_dialog_win.cc
diff --git a/ui/shell_dialogs/select_file_dialog_win.cc b/ui/shell_dialogs/select_file_dialog_win.cc
index 9e4fd48c692d78ee261ee52009370db566c1a7bd..1574f88d341dab10d9e89c67cc1fcf2ee1436f8e 100644
--- a/ui/shell_dialogs/select_file_dialog_win.cc
+++ b/ui/shell_dialogs/select_file_dialog_win.cc
@@ -17,6 +17,7 @@
 #include "base/i18n/case_conversion.h"
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/threading/thread.h"
 #include "base/win/registry.h"
 #include "base/win/scoped_comptr.h"
@@ -333,10 +334,9 @@ void SelectFileDialogImpl::SelectFileImpl(
                                      default_path, file_types, file_type_index,
                                      default_extension, BeginRun(owner),
                                      owner, params);
-  execute_params.run_state.dialog_thread->message_loop()->PostTask(
-      FROM_HERE,
-      base::Bind(&SelectFileDialogImpl::ExecuteSelectFile, this,
-                 execute_params));
+  execute_params.run_state.dialog_thread->task_runner()->PostTask(
+      FROM_HERE, base::Bind(&SelectFileDialogImpl::ExecuteSelectFile, this,
+                            execute_params));
 }
 
 bool SelectFileDialogImpl::HasMultipleFileTypeChoicesImpl() {