Attempt #4 of "Add test directory -> monorail component metadata to test"

This is a reland of 39b25a5f892c66354301b0bd505d45d5a38e6e74; the
root problem seems to have been trying to run `dirmd` on Win7,
and we've upgraded the Win7 builders to be Win10, so in theory
we won't have this issue this time.

Original change's description:
> Add test directory -> monorail component metadata to test invocations.
>
> The new ResultDB system has the ability to associate test results with
> Monorail components and teams, but in order to do that, we need to
> upload the mapping information contained in the testing/DIR_METADATA
> files along with the test results.
>
> This CL adds a gclient hook to generate the metadata in a
> ResultDB-friendly format that can be accessed by `rdb` and uploaded
> as part of a test invocation, and makes the generated data a
> dependency of the bin/run_* test scripts, to ensure that every
> test invocation will have the data.
>
> Change-Id: I83dcf7f460b6fbd1d4c23616d972510712019148
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2568896
> Commit-Queue: Dirk Pranke <dpranke@google.com>
> Reviewed-by: Chan Li <chanli@chromium.org>
> Reviewed-by: Nodir Turakulov <nodir@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#861612}

Bug: 1191087
Change-Id: I767fcbfb295723444902cfae27e25398df98b5d9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2785124
Reviewed-by: Dirk Pranke <dpranke@google.com>
Reviewed-by: Chan Li <chanli@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@google.com>
Cr-Commit-Position: refs/heads/master@{#866323}

.gitignore

@@ -280,6 +280,7 @@ vs-chromium-project.txt
 /sql/sql_unittests_run.xml
 /sync/sync.xml
 /testing/libfuzzer/fuzzer_corpus_for_bots/
+/testing/location_tags.json
 /testing/rts/
 /testserver.log
 # See third_party/.gitignore for entries covering src/third_party.

DEPS

@@ -4387,6 +4387,17 @@ hooks = [
     ],
   },
 
+  {
+    'name': 'Generate component metadata for tests',
+    'pattern': '.',
+    'action': [
+      'vpython',
+      'src/testing/generate_location_tags.py',
+      '--out',
+      'src/testing/location_tags.json',
+    ],
+  },
+
   # Download and initialize "vpython" VirtualEnv environment packages.
   {
     'name': 'vpython_common',

build/config/fuchsia/generate_runner_scripts.gni

@@ -91,6 +91,10 @@ template("fuchsia_package_runner") {
       data = []
     }
 
+    if (defined(invoker.data)) {
+      data += invoker.data
+    }
+
     wrapper_script = generated_run_pkg_script_path
 
     data_deps = [

testing/generate_location_tags.py

@@ -0,0 +1,44 @@
+#!/usr/bin/env python
+# Copyright (c) 2021 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.
+"""Generates the directory->tags mapping used by ResultDB."""
+
+# pylint: disable=line-too-long
+#
+# For more on the tags, see
+# https://source.chromium.org/chromium/infra/infra/+/master:go/src/go.chromium.org/luci/resultdb/sink/proto/v1/location_tag.proto
+#
+# pylint: enable=line-too-long
+
+import argparse
+import os
+import subprocess
+import sys
+
+THIS_DIR = os.path.dirname(__file__)
+SRC_DIR = os.path.dirname(THIS_DIR)
+BUILD_DIR = os.path.join(SRC_DIR, 'build')
+sys.path.insert(0, BUILD_DIR)
+import find_depot_tools
+
+def main():
+  parser = argparse.ArgumentParser()
+  parser.add_argument('-o', '--out', required=True,
+                      help='path to write location tag metadata to')
+  args = parser.parse_args()
+
+  exe = os.path.join(find_depot_tools.DEPOT_TOOLS_PATH, 'dirmd')
+  if sys.platform == 'win32':
+    exe = exe + '.bat'
+
+  return subprocess.call([
+    exe,
+    'location-tags',
+    '-out', args.out,
+    '-root', SRC_DIR,
+    '-repo', 'https://chromium.googlesource.com/chromium/src',
+    ])
+
+if __name__ == '__main__':
+  sys.exit(main())

testing/test.gni

@@ -78,11 +78,13 @@ template("test") {
       executable(_exec_target) {
         # Configs will always be defined since we set_defaults in BUILDCONFIG.gn.
         configs = []
-        data_deps = []
-        forward_variables_from(invoker,
-                               "*",
-                               TESTONLY_AND_VISIBILITY + _wrapper_script_vars +
-                                   [ "extra_dist_files" ])
+        forward_variables_from(
+            invoker,
+            "*",
+            TESTONLY_AND_VISIBILITY + _wrapper_script_vars + [
+                  "data_deps",
+                  "extra_dist_files",
+                ])
 
         # Thanks to the set_defaults() for test(), configs are initialized with
         # the default shared_library configs rather than executable configs.
@@ -92,6 +94,16 @@ template("test") {
         ]
         configs += [ "//build/config:executable_config" ]
 
+        if (defined(invoker.data_deps)) {
+          data_deps = invoker.data_deps
+        } else {
+          data_deps = []
+        }
+        if (!defined(data)) {
+          data = []
+        }
+        data += [ "//testing/location_tags.json" ]
+
         # Don't output to the root or else conflict with the group() below.
         output_name = rebase_path(_exec_output, root_out_dir)
       }
@@ -225,6 +237,13 @@ template("test") {
           ":$_library_target",
         ]
       }
+
+      if (defined(invoker.data_deps)) {
+        data_deps = invoker.data_deps
+      } else {
+        data_deps = []
+      }
+      data = [ "//testing/location_tags.json" ]
     }
   } else if (is_fuchsia) {
     assert(!defined(invoker.use_xvfb) || !invoker.use_xvfb)
@@ -272,6 +291,7 @@ template("test") {
       package = ":$_pkg_target"
       package_name_override = _output_name
 
+      data = [ "//testing/location_tags.json" ]
       data_deps = [ "//testing/buildbot/filters:fuchsia_filters" ]
     }
 
@@ -303,7 +323,6 @@ template("test") {
       forward_variables_from(invoker,
                              [
                                "data",
-                               "data_deps",
                                "deps",
                                "executable_args",
                                "retries",
@@ -321,6 +340,11 @@ template("test") {
       ]
 
       wrapper_output_name = "${_wrapper_output_name}"
+
+      if (!defined(data)) {
+        data = []
+      }
+      data += [ "//testing/location_tags.json" ]
     }
 
     _resources_bundle_data = target_name + "_resources_bundle_data"
@@ -391,6 +415,7 @@ template("test") {
       generated_script = "$root_build_dir/bin/run_" + invoker.target_name
       test_exe = invoker.target_name
       runtime_deps_file = _runtime_deps_file
+      data = [ "//testing/location_tags.json" ]
     }
 
     executable(target_name) {
@@ -440,6 +465,7 @@ template("test") {
         executable = "//testing/test_env.py"
         data += [ "//testing/test_env.py" ]
       }
+      data += [ "//testing/location_tags.json" ]
 
       executable_args = [
         "@WrappedPath(../../build/lacros/test_runner.py)",
@@ -515,6 +541,7 @@ template("test") {
         executable = "//testing/test_env.py"
         data += [ "//testing/test_env.py" ]
       }
+      data += [ "//testing/location_tags.json" ]
 
       executable_args = [
         "@WrappedPath(./${_executable})",
@@ -618,6 +645,8 @@ template("script_test") {
     if (defined(invoker.data)) {
       data += invoker.data
     }
+    data += [ "//testing/location_tags.json" ]
+
     data_deps = []
     if (defined(invoker.data_deps)) {
       data_deps += invoker.data_deps