message: Make framework:allocator target public.
  There is already an alias that is public in tensorflow/core.
  This is just encouraging the use of the alias.
diff: @@ -454,7 +454,7 @@ cc_library(
  "allocator.h",
  ],
  features = ["parse_headers"],
  - visibility = ["//tensorflow/core:__subpackages__"],
  + visibility = ["//visibility:public"],
  deps = [
  ":numeric_types",
  ":type_traits",
  