keystore_server: Fix crash on request window close.

The outside waiting mechanism is responsible for quitting the dialog so
prevent it from quitting itself.

keystore_server: Use B_CLOSE_ON_ESCAPE in request dialogs.

Instead of doing it manually.

Let the KeyRequestWindow return a flattened BPasswordKey.

Also provide the keyring string separately instead of abusing the
output key message.

Implement basic keyring access logic and key request dialog.

* The keyring needs to be made accessible before allowing any
operation.
* Before executing commands the keyring is made accessible if
possible (the command is aborted as needed).
* Accessing a keyring opens up a preliminary key request dialog.
* If the default keyring is accessible and a keyring key for the
requested keyring is found, that key will be used to automatically
make the requested keyring accessible.

keystore_server: Fix crash on request window close.

The outside waiting mechanism is responsible for quitting the dialog so
prevent it from quitting itself.

keystore_server: Use B_CLOSE_ON_ESCAPE in request dialogs.

Instead of doing it manually.

Let the KeyRequestWindow return a flattened BPasswordKey.

Also provide the keyring string separately instead of abusing the
output key message.

Implement basic keyring access logic and key request dialog.

* The keyring needs to be made accessible before allowing any
operation.
* Before executing commands the keyring is made accessible if
possible (the command is aborted as needed).
* Accessing a keyring opens up a preliminary key request dialog.
* If the default keyring is accessible and a keyring key for the
requested keyring is found, that key will be used to automatically
make the requested keyring accessible.