[clang] [ssaf][UnsafeBufferUsage] Add JSON serialization for UnsafeBufferUsage (PR #187156)

[Balázs Benics via cfe-commits]

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@@ -0,0 +1,88 @@
+//===---------- UnsafeBufferUsage.cpp -------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/ScalableStaticAnalysisFramework/Analyses/UnsafeBufferUsage/UnsafeBufferUsage.h"
+#include "clang/ScalableStaticAnalysisFramework/SSAFForceLinker.h" // IWYU pragma: keep
+#include "llvm/Support/Error.h"
+
+namespace {
+constexpr const char *const UnsafeBuffersKey = "UnsafeBuffers";
+} // namespace
+
+namespace clang::ssaf {
----------------
steakhal wrote:

Why do you open this namespace?
The serialize and deserialize function already use qualified names, so they would match their declarations in the ssaf namespace regardless.

```c++
using namespace clang;
using namespace ssaf;
```

https://github.com/llvm/llvm-project/pull/187156