am f87743e7: Merge "Prevent NullPointerException cases while using SipService."

* commit 'f87743e7bdfd10b9a1719036a6320a32df078879':
  Prevent NullPointerException cases while using SipService.
tree: 6c5bf9a44339fbf7064fa9ba913dcbd1736613b6
  1. cmds/
  2. include/
  3. libs/
  4. opengl/
  5. services/
  6. vpn/
  7. MODULE_LICENSE_APACHE2
  8. NOTICE