Add penghuang in //components/viz/OWNERS

Bug: None
Change-Id: Ib74322b81e40283ab84160a3f3375d98b6d5376a
Reviewed-on: https://chromium-review.googlesource.com/c/1348952Reviewed-by: Robert Kroeger <rjkroege@chromium.org>
Commit-Queue: Peng Huang <penghuang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611367}

components/viz/OWNERS

@@ -20,6 +20,7 @@ miu@chromium.org
 weiliangc@chromium.org
 rjkroege@chromium.org
 ccameron@chromium.org
+penghuang@chromium.org
 
 # display_embedder / ozone
 reveman@chromium.org