Internal error when calling base class method in inlined method without optimizations

```fsharp
type One() =
    member _.Source1 x = x

type Two() =
    inherit One()
    member inline this.Source2 x = base.Source1 x
```
optimize-
no type check errors, fails during compilation with:
error FS0073: internal error: the inline value 'Source2' was not inferred to have a known value

optimize+
compiles fine

In fsi it fails regardless of optimize switch.
