ADD_AND_TRUE_TO_LOOP_CONDITION breaks loop unrolling because LoopInfo
expects the loop condition to have been validated to be "symbol < constant"
and stayed that way.

BUG=chromium:653454
BUG=chromium:653694

Change-Id: I2057fde3a308623bd2dd7571ee878dd42b1fdac3
Reviewed-on: https://chromium-review.googlesource.com/395306Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>