[clang] [Clang] Avoid some copies in ClangAttrEmitter. NFC. (PR #193928)

[Jay Foad via cfe-commits]

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@@ -416,8 +416,8 @@ namespace {
 
   public:
     DefaultSimpleArgument(const Record &Arg, StringRef Attr,
-                          std::string T, int64_t Default)
-      : SimpleArgument(Arg, Attr, T), Default(Default) {}
+                          const std::string &T, int64_t Default)
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jayfoad wrote:

Good point. Done.

https://github.com/llvm/llvm-project/pull/193928