This fourth part of my series of patches to get rid of unsafe uses of
GetPointer takes care of the "easy" cases in VideoCommon. Three uses of
GetPointer now remain in Dolphin: VertexLoaderManager, TextureInfo, and
the software renderer's TextureSampler.
Instead, we make the event take a reference to the system and then pass
it in when the event is triggered.
This does introduce two other accessors, but these are much easier to
refactor out over time, and without modification to the existing event
interface.
This caused us to update the indirect texture information in shaders more often than we needed to, which probably doesn't matter in practice since it's only used in ubershaders and copyyscale and stride are generally only updated before EFB/XFB copies, which generally will have other changes afterwards.
As far as I can tell, it has nothing to do with the mipmap/half_scale functionality, but does change based on the width of the destination texture (and the destination texture is half the width if half_scale is set). The comment that was there (which dates back to the initial megacommit) seems to not have accounted for the width aspect; it was first used as an actual stride in bbbe898839 (the first commit that used it at all).
