message: Reduce visibility to internals of the flatbuffer repository.
  Rather than defaulting to public, default to private and explicitly mark the
  targets that should be externally visible. This causes the visibility to line up
  with what is available in the BUILD.system file.
diff: -package(
  - default_visibility = ["//visibility:public"],
  -)
  -
  licenses(["notice"]) # Apache 2.0
  exports_files(["LICENSE.txt"])
  @@ -11,7 +7,6 @@ licenses(["notice"])
  config_setting(
  name = "freebsd",
  values = {"cpu": "freebsd"},
  - visibility = ["//visibility:public"],
  )
  config_setting(
  @@ -27,6 +22,7 @@ cc_library(
  hdrs = ["//:public_headers"],
  linkstatic = 1,
  strip_include_prefix = "/include",
  + visibility = ["//visibility:public"],
  deps = ["//src:flatbuffers"],
  )
  @@ -47,12 +43,14 @@ filegroup(
  "include/flatbuffers/stl_emulation.h",
  "include/flatbuffers/util.h",
  ],
  + visibility = ["//:__subpackages__"],
  )
  # Public flatc compiler library.
  cc_library(
  name = "flatc_library",
  linkstatic = 1,
  + visibility = ["//visibility:public"],
  deps = [
  "@flatbuffers//src:flatc_library",
  ],
  @@ -71,6 +69,7 @@ cc_binary(
  "-ldl",
  ],
  }),
  + visibility = ["//visibility:public"],
  deps = [
  "@flatbuffers//src:flatc",
  ],
  @@ -96,6 +95,7 @@ cc_library(
  ],
  linkstatic = 1,
  strip_include_prefix = "/include",
  + visibility = ["//visibility:public"],
  )
  filegroup(
  @@ -114,4 +114,5 @@ filegroup(
  py_library(
  name = "runtime_py",
  srcs = [":runtime_py_srcs"],
  + visibility = ["//visibility:public"],
  )
  