Enable Gerrit support in Skia's PostUploadHook

PRESUBMIT.py

 # Copyright (c) 2013 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.
 
 
 """Top-level presubmit script for Skia.
 
 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
 for more details about the presubmit API built into gcl.
 """
@@ skipping 425 matching lines @@
   * Adds 'NOTREECHECKS=true' for non master branch changes since they do not
     need to be gated on the master branch's tree.
   * Adds 'NOTRY=true' for non master branch changes since trybots do not yet
     work on them.
   * Adds 'NOPRESUBMIT=true' for non master branch changes since those don't
     run the presubmit checks.
   * Adds extra trybots for the paths defined in PATH_TO_EXTRA_TRYBOTS.
   """
 
   results = []
-  if cl.IsGerrit():
-    results.append(
-        output_api.PresubmitNotifyResult(
-            'Post upload hooks are not yet supported for Gerrit CLs'))
-    return results
-
   atleast_one_docs_change = False
   all_docs_changes = True
   for affected_file in change.AffectedFiles():
     affected_file_path = affected_file.LocalPath()
     file_path, _ = os.path.splitext(affected_file_path)
     if 'site' == file_path.split(os.path.sep)[0]:
       atleast_one_docs_change = True
     else:
       all_docs_changes = False
     if atleast_one_docs_change and not all_docs_changes:
@@ skipping 139 matching lines @@
     state and an error if it is in 'Closed' state.
   """
   results = []
   results.extend(_CommonChecks(input_api, output_api))
   results.extend(
       _CheckTreeStatus(input_api, output_api, json_url=(
           SKIA_TREE_STATUS_URL + '/banner-status?format=json')))
   results.extend(_CheckLGTMsForPublicAPI(input_api, output_api))
   results.extend(_CheckOwnerIsInAuthorsFile(input_api, output_api))
   return results