am 7fc39b26: Merge change 25238 into eclair

Merge commit '7fc39b26fc4ec9df7d147ff34ebba90556cdb4da' into eclair-plus-aosp

* commit '7fc39b26fc4ec9df7d147ff34ebba90556cdb4da':
  Implement issue #1780928: Need support hiding nav keys.