message: Make insecure_secret_key_access public.
  This target should be public in open source Tink and is part of the normal API. Users need to implement their own mechanism to find instances (e.g. grep).
diff: @@ -755,6 +755,7 @@ cc_library(
  name = "insecure_secret_key_access",
  hdrs = ["insecure_secret_key_access.h"],
  include_prefix = "tink",
  + visibility = ["//visibility:public"],
  deps = [":secret_key_access_token"],
  )
  