workspace: Remove unused protobuf (but not libprotobuf) (RobotLocomot…

…ion#12450)

We no longer need the message generation nor compilation machinery, but we
still need the runtime support libraries for some of our deprecated methods.

Specifically, all bazel machinery for protobuf message generation is removed:
- @com_google_protobuf//...
- @drake//:protobuf
- @drake//:protobuf_python
- @drake//:protoc
- @drake//tools/skylark:drake_proto.bzl
- @protoc//...

Some runtime machinery remains, to be removed on 2020-02-01:
- @libprotobuf
- setup/mac/binary_distribution/Brewfile:brew 'protobuf'
- setup/ubuntu/source_distribution/packages-bionic.txt:python3-protobuf
- setup/ubuntu/binary_distribution/packages-bionic.txt:libprotobuf-dev

BUILD.bazel

@@ -17,21 +17,6 @@ exports_files([
     ".drake-find_resource-sentinel",
 ])
 
-alias(
-    name = "protoc",
-    actual = "@com_google_protobuf//:protoc",
-)
-
-alias(
-    name = "protobuf",
-    actual = "@com_google_protobuf//:protobuf",
-)
-
-alias(
-    name = "protobuf_python",
-    actual = "@com_google_protobuf//:protobuf_python",
-)
-
 # Drake's top-level module; all drake_py_stuff rules add this to deps.
 # (We use py_library here because drake_py_library would be circular.)
 # This file should NOT be installed (see commits in __init__.py).
@@ -57,7 +42,6 @@ install(
     deps = [
         "//bindings/pydrake:install",
         "//common:install",
-        "//common/proto:install",
         "//examples:install",
         "//lcmtypes:install",
         "//manipulation/models:install_data",

attic/multibody/BUILD.bazel

@@ -11,10 +11,6 @@ load(
     "@drake//tools/skylark:drake_cc.bzl",
     "drake_cc_package_library",
 )
-load(
-    "@drake//tools/skylark:drake_proto.bzl",
-    "drake_cc_proto_library",
-)
 load("@drake//tools/skylark:test_tags.bzl", "gurobi_test_tags")
 load("//tools/lint:lint.bzl", "add_lint_tests")
 
@@ -37,7 +33,6 @@ drake_cc_package_library(
         ":rigid_body_loop",
         ":rigid_body_tree",
         ":rigid_body_tree_alias_groups",
-        ":rigid_body_tree_alias_groups_proto",
         ":rigid_body_tree_cc",
         ":rigid_body_tree_cc_0",
         ":rigid_body_tree_cc_1",
@@ -368,21 +363,12 @@ drake_cc_library(
     ],
 )
 
-drake_cc_proto_library(
-    name = "rigid_body_tree_alias_groups_proto",
-    srcs = [
-        "alias_groups.proto",
-    ],
-    visibility = ["//visibility:private"],
-)
-
 drake_cc_library(
     name = "rigid_body_tree_alias_groups",
     srcs = ["rigid_body_tree_alias_groups.cc"],
     hdrs = ["rigid_body_tree_alias_groups.h"],
     deps = [
         ":rigid_body_tree",
-        ":rigid_body_tree_alias_groups_proto",
         "//common:essential",
     ],
 )

attic/multibody/rigid_body_tree_alias_groups.h

@@ -10,8 +10,8 @@
 
 /**
  * This class provides a way to create aliases to groups of RigidBody or
- * DrakeJoint objects. The creation of these groups can be done either
- * programmatically or via an AliasGroups protobuf config file.
+ * DrakeJoint objects. The creation of these groups can be done
+ * programmatically.
  *
  * For example, suppose we have a RigidBodyTree with 6 links named
  * [link0 ~ link5], and 6 joints [base, joint0 ~ joint4]. We can "rename"

common/proto/BUILD.bazel

@@ -37,7 +37,7 @@ drake_cc_library(
     ],
     deps = [
         "//common:essential",
-        "@com_google_protobuf//:protobuf",
+        "@libprotobuf",
     ],
 )
 
@@ -74,25 +74,6 @@ drake_py_binary(
     ],
 )
 
-_UBSAN_H = "//third_party:com_github_google_protobuf/protobuf-ubsan-fixup.h"
-
-# This library is used by //tools/skylark:drake_proto.bzl.  Developers should
-# never need to mention it directly.  The source code is placed in third_party
-# because it is forked from protobuf upstream, and thus copyright by Google.
-cc_library(
-    name = "protobuf_ubsan_fixup",
-    hdrs = [_UBSAN_H],
-    include_prefix = "drake/common/proto",
-    strip_include_prefix = "/third_party/com_github_google_protobuf",
-    tags = [
-        # Developers should not use this directly.
-        "exclude_from_package",
-        # Don't install via cc_library; instead, rely on the :install rule
-        # below to handle the install path correctly.
-        "exclude_from_libdrake",
-    ],
-)
-
 drake_cc_library(
     name = "rpc_pipe_temp_directory",
     srcs = ["rpc_pipe_temp_directory.cc"],
@@ -104,14 +85,6 @@ drake_cc_library(
     ],
 )
 
-install(
-    name = "install",
-    hdrs = [_UBSAN_H],
-    hdr_dest = "include/drake/common/proto",
-    hdr_strip_prefix = ["com_github_google_protobuf"],
-    allowed_externals = [_UBSAN_H],
-)
-
 # === test/ ===
 
 drake_cc_googletest(

setup/ubuntu/source_distribution/packages-bionic.txt

@@ -48,7 +48,6 @@ openssh-client
 patch
 patchelf
 patchutils
-protobuf-compiler
 python3-boto3
 python3-dateutil
 python3-dbg

third_party/BUILD.bazel

@@ -16,21 +16,6 @@ exports_files(
     visibility = ["@spruce//:__pkg__"],
 )
 
-exports_files(
-    [
-        "com_github_google_protobuf/LICENSE",
-        "com_github_google_protobuf/protobuf.bzl",
-    ],
-    licenses = ["notice"],  # BSD-3-Clause
-    visibility = ["@com_google_protobuf//:__pkg__"],
-)
-
-exports_files(
-    ["com_github_google_protobuf/protobuf-ubsan-fixup.h"],
-    licenses = ["notice"],  # BSD-3-Clause
-    visibility = ["//common/proto:__pkg__"],
-)
-
 exports_files(
     ["com_github_grahamdumpleton_wrapt/" + f for f in [
         "LICENSE",