[clang] [NFC][Clang] Introduce type aliases to replace use of auto in clang/lib/CodeGen/CGCall.cpp. (PR #135861)

[Tom Honermann via cfe-commits]

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@@ -199,15 +199,17 @@ static void appendParameterTypes(const CodeGenTypes &CGT,
                               prefix.size());
 }
 
+using SmallExtParameterInfoList =
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tahonermann wrote:

Done; I dropped the `Small` prefix.

With regard to the in-place size of 16, I'm guessing that was a spur of the moment pick that "felt right" way back when. I did look for other aliases of `SmallVector` for these types and that in-place size and didn't find any. There is a case of `SmallVector<CanQualType, 2>` elsewhere in the file, so it wasn't a blind default everywhere.

https://github.com/llvm/llvm-project/pull/135861