swift234

[driver] Add support for passing arguments after -- down to the frontend as-is if the driver is in immediate mode.

In Driver::translateInputArgs(), don’t break apart the OPT__DASH_DASH argument if we’re in immediate mode.
Mark OPT__DASH_DASH as being a FrontendOption.
In Swift::constructJob(), add support for types::TY_Nothing, and pass the argument for OPT__DASH_DASH as-is if the driver is invoking the frontend in immediate mode.

Swift SVN r11325