[clang] [Clang] Fix various bugs in alias CTAD transform (PR #132061)

[Younan Zhang via cfe-commits]

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@@ -3660,6 +3660,8 @@ class TreeTransform {
     return SemaRef.BuildCXXNoexceptExpr(Range.getBegin(), Arg, Range.getEnd());
   }
 
+  bool HeuristicallyComputeSizeOfPackExpr() const { return true; }
+
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zyn0217 wrote:

I choose to extract a function `ComputeSizeOfPackExprWithoutSubstitution`, since there is some common logic for extracting the pack pattern beforehand. Thus overriding `TransformSizeOfPackExpr` might not be suitable due to duplication.

(We can't add boolean parameters to the function either, as it is expanded from macros.)

https://github.com/llvm/llvm-project/pull/132061