[clang] [clang] Adding an API to create a `CXStringSet` from a Vector of `StringRef`s (PR #136773)

[Qiongsi Wu via cfe-commits]

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@@ -107,15 +107,28 @@ CXString createCXString(CXStringBuf *buf) {
   return Str;
 }
 
-CXStringSet *createSet(const std::vector<std::string> &Strings) {
+template <typename StringTy, bool Copy>
+static CXStringSet *createSetImpl(ArrayRef<StringTy> Strings) {
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qiongsiwu wrote:

Ah yes this is good to keep in mind. I revised the call in `createSet` below to avoid explicitly constructing the `ArrayRef` so I think I will opt to keep the current implementation. 

https://github.com/llvm/llvm-project/pull/136773