Infer CL author and reviewer list from local state if the issue has not previously been uploaded.

git_cl.py

Index: git_cl.py
diff --git a/git_cl.py b/git_cl.py
index eaed4baf2291a4d8822987485ef91425df000e73..e7d79dffb743d5ce0364382fda17f756ecda8084 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -1694,6 +1694,9 @@ def CMDupload(parser, args):
     cl.SetWatchers(watchlist.GetWatchersForPaths(files))
 
   if not options.bypass_hooks:
+    if options.reviewers:
+      # Set the reviewer list now so that presubmit checks can access it.
+      setattr(change, 'R', ','.join(options.reviewers))

[Ilya Sherman, 2014/03/14 01:45:33]

There's probably a better way to do this.  Thoughts?

[agable, 2014/03/14 15:11:03]

presubmit_support.py has a Change class which is capable of handling "tag
lines", i.e. lines at the end of a change description of the form R=, TBR=, and
BUG=. It saves the values of these tags into Change.tags['<tagname>']. It's also
capable of modifying those tags -- it automatically writes the R= line on upload
based on the --reviewers flags, and it automatically cleans up the R= and TBR=
lines based on who actually LGTM'd the change. You should reuse the logic there
to handle this.

[Ilya Sherman, 2014/03/18 01:18:35]

The Change class doesn't actually ever update the R= line.  That's handled by
the ChangeDescription class in this file.  I've added a method to the Change
class to update and re-parse the description.  This changes the class from an
immutable one to a mutable one.  Is that ok?

[agable, 2014/03/18 17:56:52]

You're right, I was working from faulty memory :) Your change is the right thing
to do.

     hook_results = cl.RunHook(committing=False,
                               may_prompt=not options.force,
                               verbose=options.verbose,