Nope, just the firmware in the Sony Open Device program which is part of their AOSP images set.
However, is a common mistake considering the firmware that comes with an AOSP part of it. Because it is proprietary closed-source software that delivered in binary for from the vendors mostly runs on hardware sub-systems which has nothing to do with the Linux kernel even if some of that binaries are delivered to be loaded by the kernel - but it passes to the hardware sub-system and does not run it.
If you have had read my slides, you would have learned that firmware should not considered part of the AOSP but part of the underlining OS for the specific hardware support and it delivering a supervising OS (kernel + firmware + basic root filesystem) would made the AOSP development less expensive and the hardware support more easier and more profitable for the hardware vendors and integrators.
It is possible that SFOS uses some scripts in AOSP for initialize the hardware. In that case, it should considered more an issue/lack than a feature. However, for what I saw, dd-zeroing the begin of the AOSP partition the only software that stops to work is AlienDallvik and related services but if it is not installed at all, nothing bad happens. I cannot be sure 100% about this because Android have many partitions not just one (a little less than 90, anyway).
If SFOS would have been accompanied by a functional recovery image to boot with, you could have make that test easily. Instead, you are just telling me that
Which is the huge difference of perspective between us. I have such recovery image working pretty well - because I did it - and you have not because… guess it.
spoiler: because you reacted to the cry of a random guys in the crowd!