[clang] [WIP] Implement `print-deserialized-declarations` flag to dump source… (PR #133910)

[Ilya Biryukov via cfe-commits]

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@@ -7968,6 +7968,10 @@ def print_dependency_directives_minimized_source : Flag<["-"],
   "print-dependency-directives-minimized-source">,
   HelpText<"Print the output of the dependency directives source minimizer">;
 }
+def print_deserialized_declarations : Joined<["-"],
+  "print-deserialized-declarations-path=">,
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ilya-biryukov wrote:

I wonder about the naming here... Maybe `-dump-deserialized-declaration-ranges`?
It's long, but:
- captures the meaning better (i.e. talks about ranges, not declarations)
- says dump like the `-dump-deserialized-decls`.

https://github.com/llvm/llvm-project/pull/133910