Code that needs a typehint produces not very helpful Quickfixes

This was first described here:

- https://github.com/eclipse-jdt/eclipse.jdt.core/issues/1342

Assume we have the following code:

```
public Optional notWorking() {
return CompletableFuture.completedFuture(Optional.empty()).join();
}
```

what results in an compile error: "Type mismatch: cannot convert from Optional\ to Optional\"

the first suggestion for a quickfix is to change this to an empty optional:


choosing that quickfix results in **the whole code deleted** and replaced with an empty Optional:

```
public Optional notWorking() {
return Optional.empty();
}
```