Default type parameters are handled improperly when calling methods

``` rust
pub trait Foo {
    type A;
}

pub trait Bar: Foo {
    fn foo<A, B=<Self as Foo>::A>(&self, a: A, b: B) { }
}

struct Baz;

impl Foo for Baz {
    type A = u32;
}

impl Bar for Baz { }

fn main() {
    let baz = Baz;
    Bar::foo::<u32>(&baz, 0, 0); // This works
    baz.foo::<u32>(0); // error: incorrect number of type parameters given for this method
}
```
