proto_zero_plugin [NOT FOR REVIEW].

components/tracing/proto_zero_test/BUILD.gn

+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//third_party/protobuf/proto_library.gni")
+
+proto_library("proto_zero_test_mock_messages") {
+  visibility = [ "//components/tracing/proto_zero_test/*" ]
+
+  sources = [
+    "mock_messages.proto",
+  ]
+
+  proto_out_dir = "components/tracing/proto_zero_test"
+  generator_plugin = "proto_zero_plugin"
+  generator_plugin_suffix = ".zeropb"
+  generate_cc = false
+  generate_python = false
+
+  deps = [
+    "//components/tracing/proto_zero_plugin:proto_zero_plugin($host_toolchain)",
+  ]
+}
+
+source_set("unit_tests") {
+  testonly = true
+
+  sources = [
+    "mock_messages_unittest.cc",
+  ]
+
+  deps = [
+    ":proto_zero_test_mock_messages",
+    "//base/test:test_support",
+    "//testing/gtest",
+  ]
+}