Add myself as an owner of linux desktop_aura files

R=sky

Change-Id: If5ff32465c9261b8d0a1e9b7ca839bfacff50b15
Bug: None
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1859937
Auto-Submit: Thomas Anderson <thomasanderson@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#705548}

ui/views/widget/desktop_aura/OWNERS

 per-file *x11*=thomasanderson@chromium.org
 per-file window_event_filter*=thomasanderson@chromium.org
+per-file *linux*=thomasanderson@chromium.org