Moving to HEAD of LVL master as of 5/16/18.
The LVL repo is now frozen and has been split into separate repos so
this will be the last LVL roll. Subsequent updates will have to use
the new, separate repos for layers, loader, and icd.

No changes were required to BUILD.gn with this latest update.

Bug: angleproject:2560
Change-Id: If692e4a11803318af4364fe0185fa25e2f82b790
Reviewed-on: https://chromium-review.googlesource.com/1062066
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>