auto beam issue

[Werner LEMBERG]

While working on the LM I see the following example in section 4.1.3:

```
\new Staff {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff { f8 f c }
    >>
    r4 |
  }
}
```

I now wonder why the last two notes of the temporary (lower) staff
don't have a beam, similar to the upper staff.  Is this a bug?

In case it works as intended I will change the example to not confuse
a beginner.


    Werner