BUG: iloc on DataFrame[ea]
```
from pandas.tests.extension.decimal.test_decimal import *
arr = data.__wrapped__()
ser = pd.Series(arr)
df = pd.DataFrame({"a": ser})

>>> df.iloc[:, :1]
                                                   a
0  Decimal: 0.32737812402736643502265678762341849...
1                                                   
2                                                   
3                                                   

>>> df.iloc[:, :1].values
array([[Decimal('0.32737812402736643502265678762341849505901336669921875')]],
      dtype=object)
```

Maybe slicing on the wrong axis? 