Add a simple benchmark for a TypedArray constructor. Run once with the
default pipeline and once with turbofan so that we can compare the
performance.

Also fixes a typo in the Regex for the result of the CopyWithin
benchmark which stopped the results showing up in the perf
dashboard.

BUG=

Change-Id: Ic2eb0bd1e02b458c1163e97130abd0e7531c2e1c
Reviewed-on: https://chromium-review.googlesource.com/440225Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43087}