veyron/tools/playground: Fix js testdata to use leaf dispatcher.
veyron/tools/playground: Fix js testdata to use leaf dispatcher.

Change-Id: I32c29cb44458ecf9ab06d0dc66576172e4189134

vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref