This migrates the `String` implementation from using JS interop to
explicit host imports for the standalone target.
This moves a few helper methods shared between the JS and standalone
targets to `dart:_string_helper`. This also moves the embedder regexp
implementation to `dart:_string` to be able to access internals in some
string methods (similar to how the JS implementation special-cases
`JSSyntaxRegExp`).
This removes the final real use of JS-interop in the standalone target.
So, we can:
- Remove internal JS helper libraries from the target.
- Skip JS-interop transformations in the compiler.
- Stop emitting a helper module and support script.
Because `js_interop` is imported in `dart:_wasm`, we can't remove the
library entirely. This replaces it with a stub to avoid compilation
errors, a proper removal is tracked in dartbug.com/63166.
Change-Id: Ide495c210c3a272438deebf8fe4f3f44ba314ffa
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/501960
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Kevin Moore <kevmoo@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
Simon Binder
58f9d88fb2