[NaCl SDK] Convert python scripts from optparse to argparse.

native_client_sdk/src/build_tools/buildbot_run.py

Index: native_client_sdk/src/build_tools/buildbot_run.py
diff --git a/native_client_sdk/src/build_tools/buildbot_run.py b/native_client_sdk/src/build_tools/buildbot_run.py
index 61b740ae4c14c1f5c3293c60f985a19e372427f9..5971a58c1647c36a2a851a979d4b0ba0bee38fc5 100755
--- a/native_client_sdk/src/build_tools/buildbot_run.py
+++ b/native_client_sdk/src/build_tools/buildbot_run.py
@@ -12,9 +12,9 @@ while being able to separately control excactly what the bots
 run.
 """
 
+import argparse
 import buildbot_common
 import os
-import optparse
 import subprocess
 import sys
 
@@ -101,14 +101,14 @@ def main(args):
   # orphaned .pyc files generated by a previous run.
   os.environ['PYTHONDONTWRITEBYTECODE'] = '1'
 
-  parser = optparse.OptionParser(description=__doc__)
-  parser.add_option('--build-only', action='store_true',
+  parser = argparse.ArgumentParser(description=__doc__)
+  parser.add_argument('--build-only', action='store_true',
       help='Only build the SDK, don\'t build or run tests.')
-  parser.add_option('--build-properties',
+  parser.add_argument('--build-properties',
       help='JSON properties passed by buildbot. Currently ignored.')
-  parser.add_option('--factory-properties',
+  parser.add_argument('--factory-properties',
       help='JSON properties passed by buildbot. Currently ignored.')
-  options, args = parser.parse_args(args)
+  options = parser.parse_args(args)
 
   # Skip the testing phase if we are running on a build-only bots.
   if not options.build_only: