24370b42b0
This fixes issues where structs are accessed dynamically or simply accessed in a nullable fashion, e.g. with `MyStruct? foo` dart2wasm does not yet support using structs-by-value as arguments or return values when calling linear-memory wasm functions. dart2wasm also doesn't support structs-by-value created in dart that are backed by WasmGC memory (e.g. arrays). Change-Id: I9b9c60002d2d32db3f235f1cec25fe3b35fcc17b Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/365140 Commit-Queue: Martin Kustermann <kustermann@google.com> Reviewed-by: Slava Egorov <vegorov@google.com>