Make jsbell@ and kbr@ OWNERS of modules/encoding

BUG=243354
NOTRY=true
R=dglazkov@chromium.org,abarth@chromium.org,darin@chromium.org

Review URL: https://chromiumcodereview.appspot.com/22887002

git-svn-id: svn://svn.chromium.org/blink/trunk@155945 bbb929c8-8fbe-4397-9dbb-9b2b20218538