webkitpy: Making merge-layout-test-results support --task-summary

third_party/WebKit/Tools/Scripts/merge-layout-test-results

 #!/usr/bin/python
 #
 # Copyright 2017 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 argparse
 import json
 import logging
 import os
@@ skipping 58 matching lines @@
         help='(Swarming Isolated Merge Script API) Output JSON file to create.')
     parser.add_argument(
         '--build-properties',
         help='(Swarming Isolated Merge Script API) Build property JSON file provided by recipes.')
     parser.add_argument(
         '--results-json-override-with-build-property',
         nargs=2, metavar=('RESULT_JSON_KEY', 'BUILD_PROPERTY_KEY'), default=[],
         action='append',
         help='Override the value of a value in the result style JSON file '
              '(--result-jsons-override-value layout_test_dirs /tmp/output).')
+    parser.add_argument(
+        '--summary-json',
+        help='(Swarming Isolated Merge Script API) Summary of shard state running on swarming.'
+             '(Output of the swarming.py collect --task-summary-json=XXX command.)')
 
     # Script to run after merging the directories together. Normally used with archive_layout_test_results.py
     # scripts/slave/chromium/archive_layout_test_results.py \
     #     --results-dir /b/rr/tmpIcChUS/w/layout-test-results \
     #     --build-dir /b/rr/tmpIcChUS/w/src/out \
     #     --build-number 3665 \
     #     --builder-name 'WebKit Linux - RandomOrder' \
     #     --gs-bucket gs://chromium-layout-test-archives \
     #     --staging-dir /b/c/chrome_staging \
     #     --slave-utils-gsutil-py-path /b/rr/tmpIcChUS/rw/scripts/slave/.recipe_deps/depot_tools/gsutil.py
@@ skipping 83 matching lines @@
         logging.debug('Changing directory to %s', args.output_directory)
         os.chdir(args.output_directory)
 
         post_script = list(args.post_merge_script)
         post_script.append('--result-dir', args.output_directory)
 
         logging.info('Running post merge script %r', post_script)
         os.execlp(post_script)
 
 main(sys.argv[1:])