checkor reported unsupported operand issue

[sharad1126]

Impact of the bug
checkor module where we want to check for nanoaod tiers failed on a specific workflow. Looks like the total filecount returned by the function was None.

Describe the bug

failed on pdmvserv_task_B2G-RunIISummer16NanoAODv7-02956__v1_T_200609_205933_7388 due to unsupported operand type(s) for +: 'int' and 'NoneType' and Traceback (most recent call last):
File "Unified/checkor.py", line 374, in run
self.check()
File "Unified/checkor.py", line 1041, in check
phedex_presence[output] = sum(map(lambda x: x[1], all_filecount_pb))
TypeError: unsupported operand type(s) for +: 'int' and 'NoneType'

How to reproduce it
https://github.com/CMSCompOps/WmAgentScripts/blob/master/Unified/checkor.py#L1041
wf: http://dmytro.web.cern.ch/dmytro/cmsprodmon/workflows.php?prep_id=task_B2G-RunIISummer16NanoAODv7-02956

Expected behavior
should not report this error i.e. all_filecount_pb should not be None.

Additional context and error message
@amaltaro @todor-ivanov looks like we encountered another new bug for nanoaod tier in checkor.

[sharad1126]

actually looks like more than one failed:

failed on pdmvserv_task_B2G-RunIISummer16NanoAODv7-02487__v1_T_200428_100049_5406 due to unsupported operand type(s) for +: 'int' and 'NoneType' and Traceback (most recent call last):
File "Unified/checkor.py", line 374, in run
self.check()
File "Unified/checkor.py", line 1041, in check
phedex_presence[output] = sum(map(lambda x: x[1], all_filecount_pb))
TypeError: unsupported operand type(s) for +: 'int' and 'NoneType'

[sharad1126]

#590 should be able to fix this. we are waiting to close this issue once we are satisfied.

[todor-ivanov]

The PR #590 provided by @vlimant should fix this. Thanks!