The prior CL 358522 was reverted due to relying on
moving SkArenaAlloc which does not work.
This folds in cleanup CL 358156 also.
Bug: skia:10877
Change-Id: I0a29848f0fccb7d6a8f18d307b9f6b6a0311c83a
Cq-Include-Trybots: luci.skia.skia.primary:Build-Debian10-EMCC-wasm-Release-WasmGMTests
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/358527
Commit-Queue: Adlai Holler <adlai@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>