Now we just check for each variable declared in the parameter scope whether it
occurs as a lexical variable in the body scope. This way the preparser will
also identify them.

Bug: v8:2728, v8:5064
Change-Id: I9fd96590fa431de0656c85295fd31af9b36f2e32
Reviewed-on: https://chromium-review.googlesource.com/c/1384225Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58375}