[clang] [clang][Basic] Add helper APIs to get language version codes from LangOptions (PR #163348)

[Aaron Ballman via cfe-commits]

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@@ -243,3 +243,49 @@ LLVM_DUMP_METHOD void FPOptionsOverride::dump() {
 #include "clang/Basic/FPOptions.def"
   llvm::errs() << "\n";
 }
+
+std::optional<clang::LangOptionsBase::CPlusPlusLangStd>
+LangOptions::getCPlusPlusLangStd() const {
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AaronBallman wrote:

I think it would be cleaner to put this in LangStandards.def if possible: https://github.com/llvm/llvm-project/blob/main/clang/include/clang/Basic/LangStandards.def

https://github.com/llvm/llvm-project/pull/163348