GitLab

Optimize for memory use instead of performance, to achieve parity with
the old version of tcmalloc.

BUG=724399,b:70905156

Change-Id: I11cf263b8c9595b260bf2046ab9593c2b8f66a00
Reviewed-on: https://chromium-review.googlesource.com/1130812Reviewed-by: Will Harris <wfh@chromium.org>
Commit-Queue: Gabriel Marin <gmx@chromium.org>
Cr-Commit-Position: refs/heads/master@{#586439}