am: 322b3fcccf
* commit '322b3fcccfef93726a9a9a3e14fa341e66f064bd':
Allow sample rate UNSPECIFIED to mean a route-dependent value
am: 322b3fcccf
* commit '322b3fcccfef93726a9a9a3e14fa341e66f064bd':
Allow sample rate UNSPECIFIED to mean a route-dependent value