Remove use of deprecated MessageLoop methods in ui.

ui/shell_dialogs/select_file_dialog.cc

Index: ui/shell_dialogs/select_file_dialog.cc
diff --git a/ui/shell_dialogs/select_file_dialog.cc b/ui/shell_dialogs/select_file_dialog.cc
index fd2a7cf6ce51056ca6fd1767032e1ac4ad515cc5..1aa7a0e26164079e0563943180353d03cdb6c861 100644
--- a/ui/shell_dialogs/select_file_dialog.cc
+++ b/ui/shell_dialogs/select_file_dialog.cc
@@ -7,8 +7,10 @@
 #include <stddef.h>
 
 #include "base/bind.h"
+#include "base/location.h"
 #include "base/logging.h"
-#include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "ui/shell_dialogs/select_file_dialog_factory.h"
 #include "ui/shell_dialogs/select_file_policy.h"
@@ -90,7 +92,7 @@ void SelectFileDialog::SelectFile(
     // Inform the listener that no file was selected.
     // Post a task rather than calling FileSelectionCanceled directly to ensure
     // that the listener is called asynchronously.
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE,
         base::Bind(&SelectFileDialog::CancelFileSelection, this, params));
     return;