Fix R= line rewriter to handle TBRs well.

tests/git_cl_test.py

Index: tests/git_cl_test.py
diff --git a/tests/git_cl_test.py b/tests/git_cl_test.py
index 270457d4a54a0f20669964a900ee1863ce3f1ec6..2f32bf1ef761a6b7c81b621e6db1e73b07d2cca4 100755
--- a/tests/git_cl_test.py
+++ b/tests/git_cl_test.py
@@ -692,16 +692,21 @@ class TestGitCl(TestCase):
   def test_update_reviewers(self):
     data = [
       ('foo', [], 'foo'),
+      ('foo\nR=xx', [], 'foo\nR=xx'),
+      ('foo\nTBR=xx', [], 'foo\nTBR=xx'),
       ('foo', ['a@c'], 'foo\n\nR=a@c'),
+      ('foo\nR=xx', ['a@c'], 'foo\n\nR=a@c, xx'),

[agable, 2013/08/26 17:16:45]

These test expectations changed because I realized that, when the R= line is the
last line of the description and then we trim all trailing empty lines, there's
no way to know if the original description had "foo\nR=..." or
"foo\n\n\n\nR=...", so I went with the pretty thing and put a single empty line
above the tag (see line 907 of git_cl).

+      ('foo\nTBR=xx', ['a@c'], 'foo\n\nR=a@c\nTBR=xx'),
+      ('foo\nTBR=xx\nR=yy', ['a@c'], 'foo\n\nR=a@c, yy\nTBR=xx'),
       ('foo\nBUG=', ['a@c'], 'foo\nBUG=\nR=a@c'),
-      ('foo\nR=xx\nTBR=yy\nR=bar', ['a@c'], 'foo\nTBR=a@c'),
+      ('foo\nR=xx\nTBR=yy\nR=bar', ['a@c'], 'foo\n\nR=a@c, xx, bar\nTBR=yy'),
       ('foo', ['a@c', 'b@c'], 'foo\n\nR=a@c, b@c'),
       ('foo\nBar\n\nR=\nBUG=', ['c@c'], 'foo\nBar\n\nR=c@c\nBUG='),
       ('foo\nBar\n\nR=\nBUG=\nR=', ['c@c'], 'foo\nBar\n\nR=c@c\nBUG='),
       # Same as the line before, but full of whitespaces.
       (
         'foo\nBar\n\n R = \n BUG = \n R = ', ['c@c'],
-        'foo\nBar\n\nR=c@c\n BUG =',
+        'foo\nBar\n\nR=c@c\nBUG =',
       ),
       # Whitespaces aren't interpreted as new lines.
       ('foo BUG=allo R=joe ', ['c@c'], 'foo BUG=allo R=joe\n\nR=c@c'),