Add eyaich to OWNERS

Change-Id: I506eacb30f4ca3180f175042aa3e442a728e9584
Reviewed-on: https://chromium-review.googlesource.com/c/1352517
Commit-Queue: Annie Sullivan <sullivan@chromium.org>
Reviewed-by: Caleb Rouleau <crouleau@chromium.org>
Reviewed-by: Ned Nguyen <nednguyen@google.com>
Cr-Commit-Position: refs/heads/master@{#611403}

third_party/blink/perf_tests/OWNERS

+eyaich@chromium.org
 haraken@chromium.org
 hayato@chromium.org
 nednguyen@google.com