Fix syntax highlighting for `Object` methods on `Class` variables

Consider the following:
```groovy
int m(Class c) {
  c.hashCode()
}
```

"hashCode" is shown as underlined (unknown).

![image](https://user-images.githubusercontent.com/18193802/173463770-5b843ea4-7f5b-4262-a236-f98958814f6f.png)