Create a new route between |source| and |sink|. Source and sink must be
valid, compatible (as reported by cef_media_sink_t::IsCompatibleWith), and
a route between them must not already exist. |callback| will be executed
on success or failure. If route creation succeeds it will also trigger an
asynchronous call to cef_media_observer_t::OnRoutes on all registered
observers.
Create a new route between |source| and |sink|. Source and sink must be valid, compatible (as reported by cef_media_sink_t::IsCompatibleWith), and a route between them must not already exist. |callback| will be executed on success or failure. If route creation succeeds it will also trigger an asynchronous call to cef_media_observer_t::OnRoutes on all registered observers.