Use flags from ArrObj/ArrIt when constructed from ArrObj/ArrIt

Summary: Fixes zend test.
I don't include a test, because that zend test is pretty straightforward for this one
Closes #3026

Reviewed By: @fredemmott

Differential Revision: D1400296

Pulled By: @JoelMarcey
Ignore all output after request end

Summary: `register_postsend_function` allows user code to be run after the request has
be finished. However, because these functions are just arbitrary user code,
they can produce output themselves. There is no sensible way to handle output
at this stage, and it was causing a failure in the FastCGI transport.

This patch makes transports ignore all output once onSendEnd has be called.
This means that cli behaviour is unchanged.

Fixes #2882
Closes #2923

Reviewed By: @ptarjan

Differential Revision: D1381704

Pulled By: @JoelMarcey