[release] Add json output to release tools.

tools/release/common_includes.py

 #!/usr/bin/env python
 # Copyright 2013 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
@@ skipping 720 matching lines @@
       elif line.startswith("#define V8_PATCH_LEVEL"):
         line = re.sub("\d+$", self[prefix + "patch"], line)
       elif (self[prefix + "candidate"] and
             line.startswith("#define V8_IS_CANDIDATE_VERSION")):
         line = re.sub("\d+$", self[prefix + "candidate"], line)
       output += "%s\n" % line
     TextToFile(output, version_file)
 
 
 class BootstrapStep(Step):
-  MESSAGE = "Bootstapping v8 checkout."
+  MESSAGE = "Bootstrapping v8 checkout."
 
   def RunStep(self):
     if os.path.realpath(self.default_cwd) == os.path.realpath(V8_BASE):
       self.Die("Can't use v8 checkout with calling script as work checkout.")
     # Directory containing the working v8 checkout.
     if not os.path.exists(self._options.work_dir):
       os.makedirs(self._options.work_dir)
     if not os.path.exists(self.default_cwd):
       self.Command("fetch", "v8", cwd=self._options.work_dir)
 
@@ skipping 79 matching lines @@
 
   def _Config(self):
     return {}
 
   def MakeOptions(self, args=None):
     parser = argparse.ArgumentParser(description=self._Description())
     parser.add_argument("-a", "--author", default="",
                         help="The author email used for rietveld.")
     parser.add_argument("--dry-run", default=False, action="store_true",
                         help="Perform only read-only actions.")
+    parser.add_argument("--json-output",
+                        help="File to write results summary to.")
     parser.add_argument("-r", "--reviewer", default="",
                         help="The account name to be used for reviews.")
     parser.add_argument("--sheriff", default=False, action="store_true",
                         help=("Determine current sheriff to review CLs. On "
                               "success, this will overwrite the reviewer "
                               "option."))
     parser.add_argument("-s", "--step",
         help="Specify the step where to start work. Default: 0.",
         default=0, type=int)
     parser.add_argument("--work-dir",
@@ skipping 38 matching lines @@
       return 1
 
     state_file = "%s-state.json" % self._config["PERSISTFILE_BASENAME"]
     if options.step == 0 and os.path.exists(state_file):
       os.remove(state_file)
 
     steps = []
     for (number, step_class) in enumerate([BootstrapStep] + step_classes):
       steps.append(MakeStep(step_class, number, self._state, self._config,
                             options, self._side_effect_handler))
-    for step in steps[options.step:]:
-      if step.Run():
-        return 0
+    step_summary = []
+    try:
+      for step in steps[options.step:]:
+        terminate = step.Run()
+        step_summary.append(step._text)
+        if terminate:
+          return 0
+    finally:
+      if options.json_output:
+        with open(options.json_output, "w") as f:
+          json.dump({"step_summary": step_summary}, f)
+
     return 0
 
   def Run(self, args=None):
     return self.RunSteps(self._Steps(), args)