Add ikilpatrick as core/OWNERS

Add ikilpatrick as a core OWNER following successful nomination.

NOTRY=true

Change-Id: I05211c6dc88243a7d2f9bfcc00cb3a86fb8b1a66
Reviewed-on: https://chromium-review.googlesource.com/889622
Commit-Queue: Emil A Eklund <eae@chromium.org>
Reviewed-by: Christian Biesinger <cbiesinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532099}

third_party/WebKit/Source/core/OWNERS

@@ -28,6 +28,7 @@ fs@opera.com
 futhark@chromium.org
 haraken@chromium.org
 hayato@chromium.org
+ikilpatrick@chromium.org
 inferno@chromium.org
 japhet@chromium.org
 jbroman@chromium.org