build: add recipe code for new autoroller

scripts/slave/recipes/infra/recipe_autoroller_public.py

+# 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.
+
+"""Rolls recipes.cfg dependencies for public projects."""
+
+DEPS = [
+  'recipe_autoroller',
+  'recipe_engine/properties',
+]
+
+from recipe_engine import recipe_api
+
+
+# Toposorted for best results.
+# TODO(phajdan.jr): get the list of public projects from luci-config.
+PROJECTS = [
+  'depot_tools',
+  'build',
+]
+
+
+PROPERTIES = {
+  'projects': recipe_api.Property(default=PROJECTS),
+}
+
+
+def RunSteps(api, projects):
+  api.recipe_autoroller.prepare_checkout()
+  api.recipe_autoroller.roll_projects(projects)
+
+
+def GenTests(api):
+  yield (
+      api.test('basic') +
+      api.properties(projects=['build']) +
+      api.recipe_autoroller.roll_data('build')
+  )
+
+  yield (
+      api.test('nontrivial') +
+      api.properties(projects=['build']) +
+      api.recipe_autoroller.roll_data('build', trivial=False)
+  )
+
+  yield (
+      api.test('empty') +
+      api.properties(projects=['build']) +
+      api.recipe_autoroller.roll_data('build', empty=True)
+  )
+
+  yield (
+      api.test('failure') +
+      api.properties(projects=['build']) +
+      api.recipe_autoroller.roll_data('build', success=False)
+  )