[Reland] Add aligned new/delete operators to allocator shim

This CL is a reland of [1] with a fix for when using precompiled headers.  The
object file allocator_shim.o is byte-for-byte identical to the one built at [1]
(at least on a Linux release build).

[1] https://chromium-review.googlesource.com/c/chromium/src/+/1401050

BUG=855773
R=thakis

Change-Id: Ic4321f5c1526e1ecfdffcb58cfb2687875316fa5
Reviewed-on: https://chromium-review.googlesource.com/c/1407435
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Primiano Tucci <primiano@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#622185}
2 files changed