Removes the notion of a stashed atlas that we store from the previous
flush. Now we just cache every atlas we ever render. Cached atlases
can either be 16-bit or 8-bit.
The "reuse" and "animation" cases should both behave exactly the same
as before: Where before we would copy from the stashed atlas to 8-bit
atlases, we now copy from a cached 16-bit atlas and then invalidate
it. Where before we would recycle the stashed atlas's backing texture
object, we now recycle this same texture object from an invalidated
16-bit cached atlas.
The main difference is that cases like tiled rendering now work. If
you draw your whole scene in one flush, you still get one big 16-bit
cached atlas, just like the "stashed atlas" implementation. But if you
draw your scene in tiles, you now get lots of little cached 16-bit
atlases, which can be reused and eventually copied to 8-bit atlases.
Bug: skia:8462
Change-Id: Ibae65febb948230aaaf1f1361eef9c8f06ebef18
Reviewed-on: https://skia-review.googlesource.com/c/179991
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
d6fa45472c