Unlikely. asm.js, at least in its current form, isn't a realistic compilation target for GC languages as far as I can tell.
It may be possible to compile pieces of a Dart program that don't need GC (think pure numeric computation stuff) to use asm.js and use the full JS language for the rest, but I don't know if anyone's seriously looked at doing that.
It may be possible to compile pieces of a Dart program that don't need GC (think pure numeric computation stuff) to use asm.js and use the full JS language for the rest, but I don't know if anyone's seriously looked at doing that.