For loop unrolling is not used and causes the translator fuzzer to find
a hang when unrolling tons of nested loops (duh).
Also remove MMap.h which was unused.

This is essentially a revert of https://codereview.appspot.com/4331048

BUG=chromium:665255

Change-Id: Id6940f7e306d4ed53bc992f751e9ffe733190f17
Reviewed-on: https://chromium-review.googlesource.com/412023
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>