concat does not respect order of an OrderedDict

[toobaz]

Code Sample, a copy-pastable example if possible

In [2]: from collections import OrderedDict

In [3]: pd.concat(OrderedDict([('First', pd.Series(range(3))),
   ...:                        ('Another', pd.Series(range(4)))]))
   ...:                        
Out[3]: 
Another  0    0
         1    1
         2    2
         3    3
First    0    0
         1    1
         2    2
dtype: int64

Problem description

Since the data I am passing has an order - as when I pass a list - pd.concat should respect it.

Expected Output

In [4]: pd.concat([pd.Series(range(3)), pd.Series(range(4))], keys=['First', 'Another'])
Out[4]: 
First    0    0
         1    1
         2    2
Another  0    0
         1    1
         2    2
         3    3
dtype: int64

Output of pd.show_versions()

INSTALLED VERSIONS

commit: None
python: 3.5.3.final.0
python-bits: 64
OS: Linux
OS-release: 4.9.0-6-amd64
machine: x86_64
processor:
byteorder: little
LC_ALL: None
LANG: it_IT.UTF-8
LOCALE: it_IT.UTF-8

pandas: 0.24.0.dev0+119.gc08a39fae
pytest: 3.5.0
pip: 9.0.1
setuptools: 39.2.0
Cython: 0.25.2
numpy: 1.14.3
scipy: 0.19.0
pyarrow: None
xarray: None
IPython: 6.2.1
sphinx: 1.5.6
patsy: 0.5.0
dateutil: 2.7.3
pytz: 2018.4
blosc: None
bottleneck: 1.2.0dev
tables: 3.3.0
numexpr: 2.6.1
feather: 0.3.1
matplotlib: 2.2.2.post1153+gff6786446
openpyxl: 2.3.0
xlrd: 1.0.0
xlwt: 1.3.0
xlsxwriter: 0.9.6
lxml: 4.1.1
bs4: 4.5.3
html5lib: 0.999999999
sqlalchemy: 1.0.15
pymysql: None
psycopg2: None
jinja2: 2.10
s3fs: None
fastparquet: None
pandas_gbq: None
pandas_datareader: 0.2.1

[jreback]

@toobaz can you see if we have any similar issues outstanding?

[toobaz]

@toobaz can you see if we have any similar issues outstanding?

Couldn't find any (the only vaguely related is #20909 )

What about an "order" or "sort" tagging label?