gerrit: filter out third_party/ from project names too

All the project names under third_party/ should be unique enough to chop.

BUG=chromium:384547
TEST=`gerrit mine` has tigher output

Change-Id: I00b7b17bc3f7249400b2704daec348060eb3febd
Reviewed-on: https://chromium-review.googlesource.com/203807
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Aviv Keshet <akeshet@chromium.org>
diff --git a/scripts/gerrit.py b/scripts/gerrit.py
index 85d3b28..0577ce3 100644
--- a/scripts/gerrit.py
+++ b/scripts/gerrit.py
@@ -141,7 +141,8 @@
     # Strip off common leading names since the result is still
     # unique over the whole tree.
     if not opts.verbose:
-      for pfx in ('chromeos', 'chromiumos', 'overlays', 'platform'):
+      for pfx in ('chromeos', 'chromiumos', 'overlays', 'platform',
+                  'third_party'):
         if cl['project'].startswith('%s/' % pfx):
           cl['project'] = cl['project'][len(pfx) + 1:]