For Cobalt's purpose in the past, we introduced base::Memcpy to
intercept memcpy calls and replace it with SbMemoryCopy on
Starboard/Cobalt. Recently Cobalt removed SbMemoryCopy because we found
out that memcpy implementation is universal. To reduce the cost to
maintain base::Memcpy, let us remove it and revert back to raw memcpy.

Bug: v8:10927
Change-Id: I060f191f8f1aed8b78ffe4558a3743f3a2da008b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2951462Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: John Xu <johnx@google.com>
Cr-Commit-Position: refs/heads/master@{#75070}