[clang] Delete dead value dependence check. (PR #211706)

[Eli Friedman via cfe-commits]

efriedma-quic wrote:

> (In Clang's model, we'd look at isNonOdrUse on the DeclRefExpr.)

Looked into this a bit.  isNonOdrUse is current wrong on expressions inside template arguments; ActOnConstantExpression sets the wrong markings. I briefly looked at fixing this; it doesn't seem fundamentally difficult to fix, but keeping the MaybeODRUseExprs around until we can actually resolve them properly involves passing them across a lot of different APIs.

https://github.com/llvm/llvm-project/pull/211706