[clang] [C++26] [Contracts] Initial parser support (PR #221139)

[Chuanqi Xu via cfe-commits]

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@@ -421,6 +425,9 @@ CXX11_KEYWORD(nullptr               , KEYC23)
 CXX11_KEYWORD(static_assert         , KEYMSCOMPAT|KEYC23)
 CXX11_KEYWORD(thread_local          , KEYC23)
 
+// C++26 keyword.
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ChuanqiXu9 wrote:

Done

https://github.com/llvm/llvm-project/pull/221139