This CL adapts some existing dictionary-related operations in CSA to
support SwissNameDictionary, too. This is needed to make the CSA
version of the SwissNameDictionary test suite working.

Bug: v8:11330
Change-Id: Ieb315a0806d8910e50f3643abb9a68200485e4fd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2784689
Commit-Queue: Frank Emrich <emrich@google.com>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73681}