author: Andres Salomon <dilinger@debian.org>
description: don't hardcode gn path

When building headless_shell, don't use the bundled gn binary; instead
use the gn debian system binary.

--- a/tools/licenses/licenses.py
+++ b/tools/licenses/licenses.py
@@ -806,6 +806,7 @@ def FindThirdPartyDirs(root, extra_third
 # //buildtools.
 def _GnBinary():
   exe = 'gn'
+  return exe
   if sys.platform.startswith('linux'):
     subdir = 'linux64'
   elif sys.platform == 'darwin':