Make rebase and sync the default for Gerrit updates

recipe_modules/bot_update/api.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.
 
 
 """Recipe module to ensure a checkout is consistant on a bot."""
 
 from recipe_engine import recipe_api
 
 
@@ skipping 32 matching lines @@
     return self.m.python(name, bot_update_path, cmd, **kwargs)
 
   @property
   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_no_rebase_patch_ref=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')
+    if gerrit_no_rebase_patch_ref or not gerrit_rebase_patch_ref:
+      cmd.append('--gerrit_no_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,
                       with_branch_heads=False, refs=None,
                       patch_oauth2=False, use_site_config_creds=True,
                       output_manifest=True, clobber=False,
                       root_solution_revision=None, rietveld=None, issue=None,
                       patchset=None, gerrit_no_reset=False,
-                      gerrit_rebase_patch_ref=False, **kwargs):
+                      gerrit_no_rebase_patch_ref=False,
+                      gerrit_rebase_patch_ref=True, **kwargs):
     """
     Args:
       use_site_config_creds: If the oauth2 credentials are in the buildbot
         site_config. See crbug.com/624212 for more information.
       gclient_config: The gclient configuration to use when running bot_update.
         If omitted, the current gclient configuration is used.
       rietveld: The rietveld server to use. If omitted, will infer from
         the 'rietveld' property.
       issue: The rietveld issue number to use. If omitted, will infer from
         the 'issue' property.
@@ skipping 135 matching lines @@
     if force:
       cmd.append('--force')
     if no_shallow:
       cmd.append('--no_shallow')
     if output_manifest:
       cmd.append('--output_manifest')
     if with_branch_heads or cfg.with_branch_heads:
       cmd.append('--with_branch_heads')
     if gerrit_no_reset:
       cmd.append('--gerrit_no_reset')
-    if gerrit_rebase_patch_ref:
-      cmd.append('--gerrit_rebase_patch_ref')
+    if gerrit_no_rebase_patch_ref or not gerrit_rebase_patch_ref:
+      cmd.append('--gerrit_no_rebase_patch_ref')
 
     # Inject Json output for testing.
     first_sln = cfg.solutions[0].name
     step_test_data = lambda: self.test_api.output_json(
         master, builder, slave, root, first_sln, rev_map, force,
         self._fail_patch,
         output_manifest=output_manifest, fixed_revisions=fixed_revisions)
 
     # Add suffixes to the step name, if specified.
     name = 'bot_update'
@@ skipping 60 matching lines @@
 
         # bot_update actually just sets root to be the folder name of the
         # first solution.
         if step_result.json.output['did_run']:
           co_root = step_result.json.output['root']
           cwd = kwargs.get('cwd', self.m.path['slave_build'])
           if 'checkout' not in self.m.path:
             self.m.path['checkout'] = cwd.join(*co_root.split(self.m.path.sep))
 
     return step_result