Adding mstarzinger to asmjs OWNERS.

BUG=
R=ahaas@chromium.org,mstarzinger@chromium.org

Change-Id: Ida7ac441722d778946b7ac92e8f6c7fe5ea15cdc
Reviewed-on: https://chromium-review.googlesource.com/628821
Commit-Queue: Brad Nelson <bradnelson@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47557}

src/asmjs/OWNERS

@@ -4,6 +4,7 @@ ahaas@chromium.org
 bradnelson@chromium.org
 clemensh@chromium.org
 mtrofin@chromium.org
+mstarzinger@chromium.org
 rossberg@chromium.org
 titzer@chromium.org