Repurpose GrTRecorder for storing these tasks. It's currently unused.
Reimplement on top of SkArenaAlloc and using emplace methods now that we
have C++14.
Currently it stores copy and upload tasks. In the future it will store
transfer-out commands.
Removes the optimization that reset copy-ins on clear/discard. However,
none of our existing tests exercised it.
Change-Id: I0474f77cc2d368461d542de50a7a0c5609312001
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/209643
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
24d377eedf