[array] Eagerly copy elements into a FixedArray for sorting

This CL changes Array#sort to work roughly like:
    1) Call [[Get]] on the receiver in [0, length) and store to FA
    2) Use the existing TimSort to sort that FA
    3) Call [[Set]] on the receiver in [0, length) using the result

This has the advantage that we no longer need different fast-paths
for the sorting algorithm itself, only for step 1 and 3. This results
in a code size reduction of ~2650 bytes.

This CL does not include optimizations that elides step 1 or 3.

Change-Id: I7f2e35067a6ec356add8b0c50b160d76813c536d
Reviewed-on: https://chromium-review.googlesource.com/c/1458237
Commit-Queue: Simon Zünd <szuend@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59653}