Add 'b' as a BUG= identifier for buganizer.

Buganizer is opening up for external projects too. Allow to use BUG=b:9999 to
refer to a buganizer ticket.

BUG=None
TEST=use new syntax in a CL and re-upload it

Change-Id: I733a8907fea9beb0252214338f2db16503c5b07a
Reviewed-on: https://chromium-review.googlesource.com/257831
Commit-Queue: Stefan Sauer <ensonic@google.com>
Tested-by: Stefan Sauer <ensonic@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
diff --git a/pre-upload.py b/pre-upload.py
index d858eaa..5ba3695 100755
--- a/pre-upload.py
+++ b/pre-upload.py
@@ -396,12 +396,13 @@
            'the chromium tracker in your BUG= line now.')
     return HookFailure(msg)
 
-  BUG_RE = r'\nBUG=([Nn]one|(chrome-os-partner|chromium|brillo):\d+)'
+  BUG_RE = r'\nBUG=([Nn]one|(chrome-os-partner|chromium|brillo|b):\d+)'
   if not re.search(BUG_RE, _get_commit_desc(commit)):
     msg = ('Changelist description needs BUG field (after first line):\n'
            'BUG=brillo:9999 (for Brillo tracker)\n'
            'BUG=chromium:9999 (for public tracker)\n'
            'BUG=chrome-os-partner:9999 (for partner tracker)\n'
+           'BUG=b:9999 (for buganizer)\n'
            'BUG=None')
     return HookFailure(msg)
 
diff --git a/pre-upload_unittest.py b/pre-upload_unittest.py
index c0b4ea4..5b78f1b 100755
--- a/pre-upload_unittest.py
+++ b/pre-upload_unittest.py
@@ -528,6 +528,7 @@
     """Accept a commit message w/a valid BUG."""
     self.assertMessageAccepted('\nBUG=chromium:1234\n')
     self.assertMessageAccepted('\nBUG=chrome-os-partner:1234\n')
+    self.assertMessageAccepted('\nBUG=b:1234\n')
 
   def testNone(self):
     """Accept BUG=None."""
@@ -556,6 +557,7 @@
   def testNoTrackers(self):
     """Reject commit messages w/invalid trackers."""
     self.assertMessageRejected('\nBUG=booga:1234\n')
+    self.assertMessageRejected('\nBUG=br:1234\n')
 
   def testMissing(self):
     """Reject commit messages w/no BUG line."""