This makes sure that the flag is set correctly when
surface_allocate_surface is called and client storage is disabled
properly for converted surfaces.

Use plain xrender_blit for mono -> mono copies, masking in combination
with PictOpOver doesn't make sense and doesn't work.

Fixes a Valgrind warning.

qedit: In output pin's IPin_Connect call ReceiveConnection on the receiver pin to properly negotiate media type.