[llvm] Create a EncodingConverter class with both iconv and icu support. (PR #138893)

[Hubert Tong via llvm-commits]

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@@ -0,0 +1,140 @@
+//===-- TextEncodingConverter.h - Encoding conversion class -------*- C++ -*-=//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file provides a utility class to convert between different character
+/// set encodings.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_ENCODING_CONVERTER_H
+#define LLVM_SUPPORT_ENCODING_CONVERTER_H
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hubert-reinterpretcast wrote:

Include guard should match filename.

https://github.com/llvm/llvm-project/pull/138893