This CL uses the new function pointers and generic features of Torque
to improve the performance of TypedArray.p.sort.

Instead of one Load/Store builtin that dispatches at runtime based on
the element kind, there are now many small builtins (one for each
element kind). The sorting algorithm then uses function pointers to
those small builtins, which get set once.

Changes in the relevant benchmarks:

Benchmark   Original (JS)   Current   This CL
IntTypes             83.9     202.3     240.7
BigIntTypes          32.1      47.2      53.3
FloatTypes           99.3     109.3     129.3

Bug: v8:7382
Change-Id: I8684410524d546615b19f6edcbfdc615068196aa
Reviewed-on: https://chromium-review.googlesource.com/1070069
Commit-Queue: Simon Zünd <szuend@google.com>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53322}