Razor editor doesn't recommend base.BuildRenderTree(__builder) via intellisense

Consider you have two components which you want to inherit from each other like this.

`Component1.razor`:
```razor

`Component2.razor`:
```razor
@inherits Component1
```

Now I want to render the same UI from `Component1.razor` in `Component2.razor`. This can be achieved by adding this code to `Componen2.razor`:
```razor
@{
base.BuildRenderTree(__builder);
}
```

However when you type `base.` the method `BuildRenderTree` won't get suggested by intellisense. When you type it manually, the razor editor finds the methods and displays it correctly.


Reproduce the issue with Component1.razor and Component2.razor, then trace the Razor editor's completion behavior after typing `base.`. Done means IntelliSense recommends BuildRenderTree(__builder), while the manually entered call continues to resolve and display correctly.

Written by the indexing model from the issue text.