Add neis to ast/OWNERS and parsing/OWNERS

R=littledan@chromium.org, marja@chromium.org, vogelheim@chromium.org
NOTRY=true

Review-Url: https://codereview.chromium.org/2690123003
Cr-Commit-Position: refs/heads/master@{#43196}

src/ast/OWNERS

@@ -5,5 +5,6 @@ bmeurer@chromium.org
 littledan@chromium.org
 marja@chromium.org
 mstarzinger@chromium.org
+neis@chromium.org
 rossberg@chromium.org
 verwaest@chromium.org

src/parsing/OWNERS

@@ -3,6 +3,7 @@ set noparent
 adamk@chromium.org
 littledan@chromium.org
 marja@chromium.org
+neis@chromium.org
 rossberg@chromium.org
 verwaest@chromium.org
 vogelheim@chromium.org