remove deprecated <codecvt>

Bug: chromium:358567090
Change-Id: I0480e8962ee38425406ad167f43d666b57418f5b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/360142
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Helmut Januschka <helmut@januschka.com>
Cr-Commit-Position: refs/heads/main@{#42827}
diff --git a/AUTHORS b/AUTHORS
index d838c46..9004844 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -57,6 +57,7 @@
 Graham Yoakum <gyoakum@skobalt.com>
 Gustavo Garcia <gustavogb@gmail.com>
 Hans Knoechel <hans@hans-knoechel.de>
+Helmut Januschka <helmut@januschka.com>
 Hugues Ekra <hekra01@gmail.com>
 Jake Hilton <jakehilton@gmail.com>
 James H. Brown <jbrown@burgoyne.com>
diff --git a/test/testsupport/file_utils.cc b/test/testsupport/file_utils.cc
index 4826c3b..f796361 100644
--- a/test/testsupport/file_utils.cc
+++ b/test/testsupport/file_utils.cc
@@ -20,7 +20,6 @@
 #include <windows.h>
 
 #include <algorithm>
-#include <codecvt>
 #include <locale>
 
 #include "Shlwapi.h"
diff --git a/test/testsupport/file_utils_override.cc b/test/testsupport/file_utils_override.cc
index 7d0a3e3..0140e6c 100644
--- a/test/testsupport/file_utils_override.cc
+++ b/test/testsupport/file_utils_override.cc
@@ -19,7 +19,6 @@
 #include <windows.h>
 
 #include <algorithm>
-#include <codecvt>
 #include <locale>
 
 #include "Shlwapi.h"