CFE doesn't check type arguments against the bounds of the corresponding type variables

[chloestefantsova]

Consider the following script:

void foo<T extends num>(T t) {}

class Foo<U extends num> {}

main() {
  foo("bar");
  new Foo<String>();
}

Both lines in main should result in a compile-time error, because String is not a subtype of num. However, currently it is compiled into the following without any error messages:

library;
import self as self;
import "dart:core" as core;

class Foo<U extends core::num = core::num> extends core::Object {
  synthetic constructor •() → void
    : super core::Object::•()
    ;
}
static method foo<T extends core::num = core::num>(self::foo::T t) → void {}
static method main() → dynamic {
  self::foo<core::String>("bar");
  new self::Foo::•<core::String>();
}

[chloestefantsova]

I've started working on it in CL 57621.

[chloestefantsova]

Blocked on #32130.