V8: Get build environment from MB

scripts/slave/recipes/v8.py

 # Copyright 2013 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.
 
 DEPS = [
   'archive',
   'chromium',
   'depot_tools/gclient',
   'recipe_engine/json',
   'recipe_engine/path',
@@ skipping 351 matching lines @@
         'V8 Linux - predictable',
         'bisect_one_change',
     ) +
     api.v8.fail('Mjsunit') +
     api.override_step_data(
         'Bisect.Fetch changes', api.v8.example_one_buildbot_change()) +
     api.override_step_data(
         'Bisect.Get change range',
         api.v8.example_bisection_range_one_change(),
     ) +
-
     api.time.step(120)
   )
 
   # Explicitly highlight slow tests not marked as slow.
   yield (
     api.v8.test(
         'tryserver.v8',
         'v8_linux_rel_ng_triggered',
         'slow_tests',
         requester='commit-bot@chromium.org',
         patch_project='v8',
         blamelist=['dude@chromium.org'],
-    ) + api.override_step_data(
+    ) +
+    api.override_step_data(
         'Check', api.v8.output_json(unmarked_slow_test=True))
   )
+
+  yield (
+    api.v8.test(
+        'client.v8',
+        'V8 Linux64 - builder',
+        'with_gn',
+    ) +
+    api.override_step_data(
+        'generate_build_files', api.raw_io.stream_output(
+            'Writing """\\\n'
+            'goma_dir = "/b/build/slave/cache/cipd/goma"\n'
+            'target_cpu = "x64"\n'
+            'use_goma = true\n'
+            '""" to /path/to/args.gn.\n'
+            'moar\n'))
+  )