[analyzer] Simplify logic for ExprEngine::VisitUnaryExprOrTypeTraitExpr to avoid recursion to subexpression.

This exposed bugs in the live variables analysis, and a latent analyzer bug in the SymbolReaper.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@137006 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed