Use methods from depot_tool's Changelist object instead of Rietveld RPC

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 444 matching lines @@
     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:
       break
 
   issue = cl.issue
-  rietveld_obj = cl.RpcServer()
-  if issue and rietveld_obj:
-    original_description = rietveld_obj.get_description(issue)
+  if issue:
+    original_description = cl.GetDescription()
     new_description = original_description
 
     # Add GOLD_TRYBOT_URL if it does not exist yet.
     if not re.search(r'^GOLD_TRYBOT_URL=', new_description, re.M | re.I):
       new_description += '\nGOLD_TRYBOT_URL= %s%s' % (GOLD_TRYBOT_URL, issue)
       results.append(
           output_api.PresubmitNotifyResult(
               'Added link to Gold trybot runs to the CL\'s description.\n'
               'Note: Results may take sometime to be populated after trybots '
               'complete.'))
@@ skipping 14 matching lines @@
         r'^DOCS_PREVIEW=.*', new_description, re.M | re.I):
       # Automatically add a link to where the docs can be previewed.
       new_description += '\nDOCS_PREVIEW= %s%s' % (DOCS_PREVIEW_URL, issue)
       results.append(
           output_api.PresubmitNotifyResult(
               'Automatically added a link to preview the docs changes to the '
               'CL\'s description'))
 
     # If the target ref is not master then add NOTREECHECKS=true and NOTRY=true
     # to the CL's description if it does not already exist there.
-    target_ref = rietveld_obj.get_issue_properties(issue, False).get(
-        'target_ref', '')
-    if target_ref != 'refs/heads/master':
+    target_ref = cl.GetRemoteBranch()[1]
+    if target_ref != 'refs/remotes/origin/master':
       if not re.search(
           r'^NOTREECHECKS=true$', new_description, re.M | re.I):
         new_description += "\nNOTREECHECKS=true"
         results.append(
             output_api.PresubmitNotifyResult(
                 'Branch changes do not need to rely on the master branch\'s '
                 'tree status. Automatically added \'NOTREECHECKS=true\' to the '
                 'CL\'s description'))
       if not re.search(
           r'^NOTRY=true$', new_description, re.M | re.I):
@@ skipping 21 matching lines @@
                   'Your CL modifies the path %s.\nAutomatically adding %s to '
                   'the CL description.' % (affected_file_path, extra_bots)))
           _MergeCQExtraTrybotsMaps(
               cq_master_to_trybots, _GetCQExtraTrybotsMap(extra_bots))
     if cq_master_to_trybots:
       new_description = _AddCQExtraTrybotsToDesc(
           cq_master_to_trybots, new_description)
 
     # If the description has changed update it.
     if new_description != original_description:
-      rietveld_obj.update_description(issue, new_description)
+      cl.UpdateDescription(new_description)
 
     return results
 
 
 def _AddCQExtraTrybotsToDesc(cq_master_to_trybots, description):
   """Adds the specified master and trybots to the CQ_INCLUDE_TRYBOTS keyword.
 
   If the keyword already exists in the description then it appends to it only
   if the specified values do not already exist.
   If the keyword does not exist then it creates a new section in the
@@ skipping 46 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