[BUG] Creating DataFrames or Series with only None/null entries results in 0-length

[randerzander]

Creating a cudf.Series or cudf.DataFrame with a Series of only None values results in incorrect row-length

Repro #1:

import cudf
print(cudf.Series([None, None, None]))

Result:

<empty Series of dtype=float64>

The above should be a Series of length 3

Repro #2:

df = cudf.DataFrame()
df['a'] = [None, None, None]
df

Result:

<cudf.DataFrame ncols=1 nrows=0 >

The above should be a df with 3 rows.