Fixes https://github.com/dart-lang/sdk/issues/56905
Instead of just supporting isJSAny and isJSObject, we
can support isA for all objects. Depending on the static
type, we include an intrinsic _isJSAny function first in
the transformation. For fast paths for JSObjects, we also
now call an intrinsic function which has the added benefit
of now correctly returning true for objects with no prototype.
The intrinsic functions in dart2wasm need to be careful to
not treat ExternalDartReferences as JS values, so JSValue
is amended to include a field that determines if the value
is a Dart value (and caches it if not set already). JSValue
constructions are updated to pass false for this field if
we know for sure this value isn't an externalized Dart value.
CoreLibraryReviewExempt: Backend-specific function changes.
Change-Id: Ib2a6e74b4130632791375fcda9a5b85198ad64af
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/478241
Commit-Queue: Srujan Gaddam <srujzs@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Srujan Gaddam
9f367b1709