Improve SAM type closure parameter type inferencing

Consider the following:
```java
@FunctionalInterface
interface Sam {
  int meth(int a, Long b, java.util.regex.Pattern c);
}
```

```groovy
// both cases should inference 'a' as int, 'b' as Long and 'c' as Pattern
Sam type = { a, b, c -> ... }
def type = { a, b, c -> ... } as Sam
```