Fix setbotcommit comment on ambiguous revision

Add revision number option to gerrit_client.py setbotcommit command. Add
an explicit revision number to a setbotcommit call in the update_files
method.

After creating a new patch-set in the release recipe and verifying it
was created we are adding a comment which could be applied to the
previous patch. Setting `Bot-Commit+1` relied on the default 'current'
revision which may be stale in some Gerrit replicas. This CL applies the
fix suggested in 412739202

Bug: 414681998
Change-Id: I1d380e221864bcf1183c77fa58be4ede9a787ef1
Recipe-Nontrivial-Roll: build_internal
Recipe-Nontrivial-Roll: chrome_release
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/6718447
Reviewed-by: Alex Kravchuk <alexanderkr@google.com>
Reviewed-by: Scott Lee <ddoman@chromium.org>

gerrit_client.py

@@ -383,9 +383,18 @@ def CMDgetcommitincludedin(parser, args):
 def CMDsetbotcommit(parser, args):
     """Sets bot-commit+1 to a bot generated change."""
     parser.add_option('-c', '--change', type=int, help='change number')
+    parser.add_option(
+        '-r',
+        '--revision',
+        type=str,
+        default='current',
+        help='revision ID. See '
+        'https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#revision-id '  # pylint: disable=line-too-long
+        'for acceptable format')
     (opt, args) = parser.parse_args(args)
     result = gerrit_util.SetReview(urllib.parse.urlparse(opt.host).netloc,
                                    opt.change,
+                                   opt.revision,
                                    labels={'Bot-Commit': 1},
                                    ready=True)
     logging.info(result)

recipes/recipe_modules/gerrit/api.py

@@ -558,13 +558,16 @@ class GerritApi(recipe_api.RecipeApi):
       publish_command.append('--verbose')
     self('publish edit', publish_command)
 
+    NEW_PATCHSET_REVISION_NUMBER = 2
     # Make sure the new patchset is propagated to Gerrit backend.
     with self.m.step.nest('verify the patchset exists on CL %d' % change):
       retries = 0
       max_retries = 2
       while retries <= max_retries:
         try:
-          if self.get_revision_info(host, change, 2):
+          if self.get_revision_info(host,
+                                    change,
+                                    patchset=NEW_PATCHSET_REVISION_NUMBER):
             break
         except self.m.step.InfraFailure:
           if retries == max_retries:  # pragma: no cover
@@ -580,6 +583,8 @@ class GerritApi(recipe_api.RecipeApi):
           host,
           '--change',
           change,
+          '--revision',
+          NEW_PATCHSET_REVISION_NUMBER,
       ]
       if verbose:
         set_bot_commit_command.append('--verbose')

recipes/recipe_modules/gerrit/examples/full.expected/basic.json

@@ -384,6 +384,8 @@
       "https://chromium-review.googlesource.com",
       "--change",
       "91827",
+      "--revision",
+      "2",
       "--verbose"
     ],
     "env": {