Child Injector JIT Singletons Not Eager

_From [sberlin](https://code.google.com/u/sberlin/) on June 11, 2009 18:51:29_

Similar to issue 373 , but this time with implicit singletons.

Consider:

`@`Singleton class A { `@`Inject A(B b) {} }
`@`Singleton class B { }

AbstractModule {
 configure() {
    bind(A.class);
 }
}

If the module is used in a parent injector, B is eagerly constructed.  If
it's used in a child injector, B is not eagerly constructed.

FWIW, the patch I have attached to issue 38 can be used to fix this problem
(introducing a concept of listening to bindings, which can be used to
immediately instantiating singletons if they're supposed to be eager).

_Original issue: http://code.google.com/p/google-guice/issues/detail?id=386_