my_activity.py: Add a shorturl for cromium-os.

This fix adds the crosbug.com shorturl scheme for the chromium-os project.

BUG=None
TEST=manual run of ./my_activity.py


Review URL: https://chromiumcodereview.appspot.com/12226135

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@182300 0039d316-1c4b-4281-b951-d872f2087c98

my_activity.py

@@ -132,6 +132,7 @@ google_code_projects = [
   },
   {
     'name': 'chromium-os',
+    'shorturl': 'crosbug.com',
   },
   {
     'name': 'chrome-os-partner',