Add tkchin to video_coding OWNERS.
Add tkchin to video_coding OWNERS.

BUG=
R=stefan@webrtc.org

Review URL: https://codereview.webrtc.org/1217853006.

Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#9528}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: d830aeafe943b498fd0db51f949dc183be3b4e4f

aleonliao/webrtc-trunk,jchavanton/webrtc,aleonliao/webrtc-trunk,jchavanton/webrtc,aleonliao/webrtc-trunk,sippet/webrtc,aleonliao/webrtc-trunk,aleonliao/webrtc-trunk,jchavanton/webrtc,sippet/webrtc,sippet/webrtc,Alkalyne/webrtctrunk,Alkalyne/webrtctrunk,sippet/webrtc,Alkalyne/webrtctrunk,aleonliao/webrtc-trunk,Alkalyne/webrtctrunk,Alkalyne/webrtctrunk,Alkalyne/webrtctrunk,jchavanton/webrtc,jchavanton/webrtc,sippet/webrtc,jchavanton/webrtc,jchavanton/webrtc,Alkalyne/webrtctrunk,sippet/webrtc,Alkalyne/webrtctrunk