This change implements recursive closure captures. This permits
cases like the following
{
function f() { g(); }
function g() { f(); }
}
and the slightly more useful
class C {
this.x = 42;
this.f = () => x;
}
To do this requires caching the environment objects and permitting
cycles in the resulting environment graph. The closure emitter code
already knows how to handle this.
In addition, we must mark captures of `this` as free variables.
This resolvespulumi/pulumi-fabric#333.
8ce07617c9