Add apply_gerrit_ref to bot_update api.

BUG=skia:5627

Review-Url: https://codereview.chromium.org/2249983004

recipe_modules/bot_update/api.py

@@ -53,6 +53,27 @@ class BotUpdateApi(recipe_api.RecipeApi):
   def last_returned_properties(self):
       return self._last_returned_properties
 
+  # DO NOT USE.
+  # The below method will be removed after there are no more callers of
+  # tryserver.maybe_apply_issue (skbug.com/5588).
+  def apply_gerrit_ref(self, root, gerrit_no_reset=False,
+                       gerrit_rebase_patch_ref=True, **kwargs):
+    apply_gerrit_path = self.resource('apply_gerrit.py')
+    kwargs.setdefault('infra_step', True)
+    kwargs.setdefault('env', {}).setdefault('PATH', '%(PATH)s')
+    kwargs['env']['PATH'] = self.m.path.pathsep.join([
+        kwargs['env']['PATH'], str(self._module.PACKAGE_REPO_ROOT)])
+    cmd = [
+        '--gerrit_repo', self._repository,
+        '--gerrit_ref', self._gerrit_ref or '',
+        '--root', str(root),
+    ]
+    if gerrit_no_reset:
+      cmd.append('--gerrit_no_reset')
+    if gerrit_rebase_patch_ref:
+      cmd.append('--gerrit_rebase_patch_ref')
+    return self.m.python('apply_gerrit', apply_gerrit_path, cmd, **kwargs)
+
   def ensure_checkout(self, gclient_config=None, suffix=None,
                       patch=True, update_presentation=True,
                       force=False, patch_root=None, no_shallow=False,

recipe_modules/bot_update/example.expected/apply_gerrit_ref.json

@@ -0,0 +1,26 @@
+[
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "RECIPE_MODULE[depot_tools::bot_update]/resources/apply_gerrit.py",
+      "--gerrit_repo",
+      "chromium",
+      "--gerrit_ref",
+      "",
+      "--root",
+      "/tmp/test/root",
+      "--gerrit_no_reset",
+      "--gerrit_rebase_patch_ref"
+    ],
+    "env": {
+      "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]"
+    },
+    "name": "apply_gerrit"
+  },
+  {
+    "name": "$result",
+    "recipe_result": null,
+    "status_code": 0
+  }
+]

recipe_modules/bot_update/example.py

@@ -35,6 +35,13 @@ def RunSteps(api):
   suffix = api.properties.get('suffix')
   gerrit_no_reset = True if api.properties.get('gerrit_no_reset') else False
   gerrit_rebase_patch_ref = bool(api.properties.get('gerrit_rebase_patch_ref'))
+
+  if api.properties.get('test_apply_gerrit_ref'):
+    api.bot_update.apply_gerrit_ref(
+        root='/tmp/test/root',
+        gerrit_no_reset=gerrit_no_reset,
+        gerrit_rebase_patch_ref=gerrit_rebase_patch_ref)
+  else:
     api.bot_update.ensure_checkout(
         force=force,
         no_shallow=no_shallow,
@@ -163,6 +170,12 @@ def GenTests(api):
       slavename='somehost',
       gerrit_rebase_patch_ref=True
   )
+  yield api.test('apply_gerrit_ref') + api.properties(
+      repository='chromium',
+      gerrit_rebase_patch_ref=True,
+      gerrit_no_reset=1,
+      test_apply_gerrit_ref=True,
+  )
   yield api.test('tryjob_v8') + api.properties(
       mastername='tryserver.chromium.linux',
       buildername='linux_rel',

recipe_modules/bot_update/resources/apply_gerrit.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python
+# 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.
+
+import optparse
+import sys
+
+import bot_update  # pylint: disable=relative-import
+
+
+if __name__ == '__main__':
+  parse = optparse.OptionParser()
+
+  parse.add_option('--gerrit_repo',
+                   help='Gerrit repository to pull the ref from.')
+  parse.add_option('--gerrit_ref', help='Gerrit ref to apply.')
+  parse.add_option('--root', help='The location of the checkout.')
+  parse.add_option('--gerrit_no_reset', action='store_true',
+                   help='Bypass calling reset after applying a gerrit ref.')
+  parse.add_option('--gerrit_rebase_patch_ref', action='store_true',
+                   help='Rebase Gerrit patch ref after of checking it out.')
+
+  options, _ = parse.parse_args()
+
+  sys.exit(
+      bot_update.apply_gerrit_ref(
+          options.gerrit_repo,
+          options.gerrit_ref,
+          options.root,
+          not options.gerrit_no_reset,
+          options.gerrit_rebase_patch_ref)
+  )