Bug: Accessing private statics in a class via its derived class is allowed

TypeScript Version:

1.8.X

Code

class FooBase {
    private static privateStatic: string = "";

    testBase(): void {
        console.log(FooBase.privateStatic);

        // Should error, but doesn't
        console.log(Foo.privateStatic);
   }
}

class Foo extends FooBase {
    test() {
        // Should error, and does
        console.log(Foo.privateStatic);
    }
}

Expected behavior:
Accessing Foo.privateStatic shouldn't be allowed, regardless of the context it's called in.

Actual behavior:
FooBase is allowed to do this.

(thanks @sethbrenith for deducing this)

Start by reproducing the supplied FooBase/Foo code with the TypeScript 1.8.x checker and compare the two private static accesses. Trace the type-checking path for static member visibility; done means both accesses to Foo.privateStatic produce the expected error, including the one inside FooBase.