[clang] [Clang] [C++26] Expansion Statements (Part 1: AST) (PR #169680)

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Sirraide wrote:

Ok, I’ve merged all of the `CXXExpansionStmtPattern` classes into a single class (which is now rather huge as a result, but it ends up being less code overall), and I’ve merged the two select exprs into a single one by just synthesising an `InitListExpr` to store all of the bindings of a destructuring expansion statement.

Including the Decl, we’re now down to 4 AST nodes in total, which is a lot less horrible.

https://github.com/llvm/llvm-project/pull/169680