Merge \"docs: Added AfW item to DP4 \"Behavior Changes\" page\" into nyc-dev

  <li>The Work Mode setting controls access to work apps. When work mode is off the

  system launcher indicates work apps are unavailable by greying them out. Enabling

  work mode again restores normal behavior.

  work mode again restores normal behavior.</li>

  <li>When installing a PKCS #12 file containing a client certificate chain and

  the corresponding private key from Settings UI, the CA certificate in the

  chain is no longer installed to the trusted credentials storage. This does

  not affect the result of {@link android.security.KeyChain#getCertificateChain

  KeyChain.getCertificateChain()} when apps attempt to retrieve the client

  certificate chain later. If required, the CA certificate should be installed

  to the trusted credentials storage via Settings UI separately, with a

  DER-encoded format under a .crt or .cer file extension.

  </li>

</ul>

<p>