[clang-tools-extra] [clang-tidy] Add misc-shadowed-namespace-function check (PR #168406)

[Yanzuo Liu via cfe-commits]

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@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MISC_SHADOWEDNAMESPACEFUNCTIONCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MISC_SHADOWEDNAMESPACEFUNCTIONCHECK_H
+
+#include "../ClangTidyCheck.h"
+#include <tuple>
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zwuis wrote:

Should be moved to `.cpp`.

https://github.com/llvm/llvm-project/pull/168406