commandline: flip add_option_group and add_argument_group

We added a compatibility wrapper for add_option_group so code would
transparently use argparse instead, but since we've killed off the
optparse module in most places now, invert the compatibility logic
so everyone uses the argparse API naming.

BUG=chromium:496565
TEST=precq passes

Change-Id: Ie7e0c49d11df02a03311d3a3853874c8f7ecfc1c
Reviewed-on: https://chromium-review.googlesource.com/612055
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
diff --git a/scripts/cbuildbot.py b/scripts/cbuildbot.py
index 89a8718..a82ea6f 100644
--- a/scripts/cbuildbot.py
+++ b/scripts/cbuildbot.py
@@ -468,7 +468,7 @@
                         'If no branch is specified the current branch of the '
                         'project will be used.')
 
-  parser.add_option_group(group)
+  parser.add_argument_group(group)
 
   #
   # Remote trybot options.
@@ -508,7 +508,7 @@
   group.add_option('--committer-email', type='string',
                    help='Override default git committer email.')
 
-  parser.add_option_group(group)
+  parser.add_argument_group(group)
 
   #
   # Branch creation options.
@@ -531,7 +531,7 @@
                           help='Do not actually push to remote git repos.  '
                                'Used for end-to-end testing branching.')
 
-  parser.add_option_group(group)
+  parser.add_argument_group(group)
 
   #
   # Advanced options.
@@ -668,7 +668,7 @@
                           api=constants.REEXEC_API_SANITY_CHECK_BUILD,
                           help='Run the build as a sanity check build.')
 
-  parser.add_option_group(group)
+  parser.add_argument_group(group)
 
   #
   # Internal options.
@@ -743,7 +743,7 @@
                                'specifying a file with a pickle of the result '
                                'to be returned.')
 
-  parser.add_option_group(group)
+  parser.add_argument_group(group)
 
   #
   # Debug options