[clang] [alpha.webkit.UncountedLocalVarsChecker] Allow uncounted object references within trivial statements (PR #82229)

[Ryosuke Niwa via cfe-commits]

rniwa wrote:

Actually, we need to cache the results for `VisitDeclRefExpr` as well to avoid infinite recursion.

https://github.com/llvm/llvm-project/pull/82229