This CL introduces Torque classes with fields around TypedArrays so
CSA LoadObjectField accessors that are only used in Torque code
can be removed.

R=tebbi@chromium.org

Bug: v8:8562
Change-Id: Ie46dad5c25bd6ac03aacef8509e22f435896d127
Reviewed-on: https://chromium-review.googlesource.com/c/1451823Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Simon Zünd <szuend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59359}