[clang] [clang][dataflow] Discard unneeded `ExprToLoc` and `ExprToVal` entries. (PR #72850)

[via cfe-commits]

martinboehme wrote:

After some internal discussion with @ymand, I think I'd like to retract this PR in favor of https://github.com/llvm/llvm-project/pull/72985.

I will still keep this PR open for the time being however, until we've resolved the discussion.

https://github.com/llvm/llvm-project/pull/72850