Add GN (the build tool) to the chromium.linux buildbots and try jobs

scripts/slave/recipes/chromium_gn.py

+# Copyright 2014 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 = [
+  'chromium',
+  'gclient',
+  'platform',
+  'properties',
+]
+
+
+def GenSteps(api):
+  api.gclient.set_config('chromium')
+  yield api.gclient.checkout(revert=True)
+
+
+  # TODO(dpranke): The build_config should probably be a property passed
+  # in from slaves.cfg, but that doesn't exist today, so we need a lookup
+  # mechanism to map bot name to build_config.
+  build_config = {
+    'Linux GN (dbg)': 'Debug',
+  }[api.properties.get('buildername')]

[iannucci, 2014/03/27 01:33:57]

yeah, we need a real mechanism for this. Bug filed here of how we might do this:
crbug.com/356974

+
+  api.chromium.set_config('chromium', BUILD_CONFIG=build_config)
+  yield api.chromium.runhooks(run_gyp=False)
+
+  # TODO(dpranke): GN doesn't support absolute paths for the -o arg
+  # so we have to pass the path relative to the checkout root.
+  yield api.chromium.run_gn('out/' + build_config)

[iannucci, 2014/03/27 01:33:57]

Oh, that's actually worse than I thought :D. I guess we don't even have the
'out' string available in a non-absolute path form.

+
+  yield api.chromium.compile_with_ninja('compile', api.chromium.output_dir)
+
+  # TODO(dpranke): crbug.com/353854. Run gn_unittests and other tests
+  # when they are also being run as part of the try jobs.
+
+
+def GenTests(api):
+  yield (
+      api.test('unittest_basic') +
+      api.properties.generic(buildername='Linux GN (dbg)') +
+      api.platform.name('linux')
+  )
+
+  # TODO(dpranke): This test should actually produce the same result
+  # as the previous test, but it specifically matches what is run
+  # on the "Linux GN (dbg)" bot. We should have one 'simulation' test
+  # for each bot config. Ideally this should live somewhere else
+  # closer to the master tests.
+  yield (
+      api.test('full_chromium_linux_Linux_GN__dbg_') +
+      api.properties.generic(buildername='Linux GN (dbg)') +
+      api.platform.name('linux')
+  )