tree 3059fc75c0638b47f19103b214f1ec2e82f7229e
parent bde8430b972007f62b044664a02950bdfa0f2353
author Aske Simon Christensen <askesc@google.com> 1660893078 +0000
committer Commit Bot <commit-bot@chromium.org> 1660893078 +0000

[dart2wasm] Implement the three-pronged WasmGC type hierarchy.

This splits the type hierarchy into three separate hierarchies with
the top types `any`, `func` and `extern`.

Update d8 to 10.6.91, which switches to the new type hierarchy.

Also, all ref shorthands for abstract heap types are now nullable, so
the type emitter in the `wasm_builder` is updated to follow that scheme.

To reduce confusion about the nullability of abstract reference types,
these now all require the nullability to be specified explicitly.

Change-Id: I4774d08cbed18307e481c466b2e3402a8d8fb6bd
Cq-Include-Trybots: luci.dart.try:dart2wasm-linux-x64-d8-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/255060
Reviewed-by: Joshua Litt <joshualitt@google.com>