We had issues when combining host and guest presentation since certain configurations in guest presentation such as double buffering were very unoptimal for the host and would significantly affect the FPS. As a result of this, we've now made host presentation have its own presentation textures which are copied into from the guest at presentation time, allowing us to change parameters of the host presentation independently of the guest.
We've implemented the infrastructure for this which includes being able to create images from host GPU memory using VMA, an optimized linear texture sync and a method to do on-GPU texture-to-texture copies.
We've also moved to driving the V-Sync event using AChoreographer on its on thread in this PR, which more accurately encapsulates HOS behavior and allows games such as ARMS to boot as they depend on the V-Sync event being signalled even when the game isn't presenting.
This commit makes GraphicBufferProducer significantly more accurate by matching the behavior of AOSP alongside mirroring the tweaks made by Nintendo.
It eliminates a lot of the magic structures and enumerations used prior and replaces them with the correct values from AOSP or HOS.
There was a lot of functional inaccuracy as well which was fixed, we emulate the exact subset of HOS behavior that we need to. A lot of the intermediate layers such as GraphicBufferConsumer or Gralloc/Sync are not emulated as they're pointless abstractions here.
We decided to restructure Skyline to draw a layer of separation between guest and host GPU. We're reserving the `gpu` namespace and directory for purely host GPU and creating a new `soc` directory and namespace for emulation of parts of the X1 SoC which is currently limited to guest GPU but will be expanded to contain components like the audio DSP down the line.
