[lacros] Generate a test runner wrapper for lacros

This CL generates a wrapper for each test target of format:
"bin/run_{target}", and the wrapper then invokes the lacros test
runner.

Bug: 1104318
Change-Id: I0e33e745068fe08173e077a593a3c83501bf9fb2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2295925
Commit-Queue: Yuke Liao <liaoyuke@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Reviewed-by: Erik Chen <erikchen@chromium.org>
Reviewed-by: Sven Zheng <svenzheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#788823}

build/lacros/OWNER

+svenzheng@chromium.org
+liaoyuke@chromium.org
+erikchen@chromium.org

build/lacros/test_runner.py

+#!/usr/bin/env vpython
+#
+# Copyright 2020 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.
+"""This script facilitates running tests for lacros.
+
+WARNING: currently, this script only supports running test targets that do not
+require a display server, such as base_unittests and url_unittests.
+TODO(crbug.com/1104318): Support test targets that require a display server by
+using ash_chrome.
+"""
+
+import argparse
+import subprocess
+import sys
+
+
+def _ParseArguments():
+  arg_parser = argparse.ArgumentParser()
+  arg_parser.usage = __doc__
+
+  arg_parser.add_argument(
+      'command',
+      help='Command to execute the tests. For example: "./url_unittests')
+
+  args = arg_parser.parse_known_args()
+  return args[0], args[1]
+
+
+def Main():
+  args, forward_args = _ParseArguments()
+  return subprocess.call([args.command] + forward_args)
+
+
+if __name__ == '__main__':
+  sys.exit(Main())

testing/test.gni

@@ -6,6 +6,8 @@
 # TEST SETUP
 # ==============================================================================
 
+import("//build/config/chromeos/ui_mode.gni")
+
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/extract_unwind_tables.gni")
@@ -29,7 +31,8 @@ if (is_ios) {
   import("//build/config/ios/rules.gni")
 }
 
-if ((is_linux && !is_chromeos) || is_mac || is_win) {
+if ((is_linux && !is_chromeos) || is_mac || is_win ||
+    chromeos_is_browser_only) {
   import("//build/config/sanitizers/sanitizers.gni")
   import("//build/util/generate_wrapper.gni")
 }
@@ -376,6 +379,48 @@ template("test") {
         "//build/win:default_exe_manifest",
       ]
     }
+  } else if (chromeos_is_browser_only) {
+    _runtime_deps_file = "$root_out_dir/${target_name}.runtime_deps"
+    _executable = target_name
+    _gen_runner_target = "${target_name}__runner"
+
+    generate_wrapper(_gen_runner_target) {
+      testonly = true
+      wrapper_script = "$root_build_dir/bin/run_" + _executable
+      executable = "//build/lacros/test_runner.py"
+      executable_args = [
+        "@WrappedPath(./${_executable})",
+        "--test-launcher-bot-mode",
+      ]
+      if (is_asan) {
+        executable_args += [ "--asan=true" ]
+      }
+      if (is_msan) {
+        executable_args += [ "--msan=true" ]
+      }
+      if (is_tsan) {
+        executable_args += [ "--tsan=true" ]
+      }
+      if (use_cfi_diag) {
+        executable_args += [ "--cfi-diag=true" ]
+      }
+
+      data = [
+        "//testing/test_env.py",
+        "//.vpython",
+      ]
+    }
+
+    executable(target_name) {
+      forward_variables_from(invoker, "*")
+      if (!defined(deps)) {
+        deps = []
+      }
+
+      testonly = true
+      write_runtime_deps = _runtime_deps_file
+      deps += [ ":$_gen_runner_target" ]
+    }
   } else {
     if ((is_linux && !is_chromeos) || is_mac || is_win) {
       _runtime_deps_file = "$root_out_dir/${target_name}.runtime_deps"