[23.1] Fix and prevent persisting null file_size

[mvdbeek]

This can happen in extended metadata mode.
Fixes:

TypeError: float() argument must be a string or a number, not 'NoneType'
  File "galaxy/jobs/mapper.py", line 258, in __cache_job_destination
    self.cached_job_destination = self.__determine_job_destination(
  File "galaxy/jobs/mapper.py", line 242, in __determine_job_destination
    job_destination = self.__handle_dynamic_job_destination(raw_job_destination)
  File "galaxy/jobs/mapper.py", line 205, in __handle_dynamic_job_destination
    return self.__handle_rule(expand_function, destination)
  File "galaxy/jobs/mapper.py", line 220, in __handle_rule
    raise e
  File "galaxy/jobs/mapper.py", line 209, in __handle_rule
    job_destination = self.__invoke_expand_function(rule_function, destination)
  File "galaxy/jobs/mapper.py", line 125, in __invoke_expand_function
    return expand_function(**actual_args)
  File "tpv/rules/gateway.py", line 51, in map_tool_to_destination
    return ACTIVE_DESTINATION_MAPPER.map_to_destination(app, tool, user, job, job_wrapper, resource_params,
  File "tpv/core/mapper.py", line 168, in map_to_destination
    evaluated_entity = self.match_combine_evaluate_entities(context, tool, user)
  File "tpv/core/mapper.py", line 138, in match_combine_evaluate_entities
    evaluated_entity = combined_entity.evaluate_rules(context)
  File "tpv/core/entities.py", line 488, in evaluate_rules
    if rule.is_matching(context):
  File "tpv/core/entities.py", line 742, in is_matching
    if self.loader.eval_code_block(self.match, context):
  File "tpv/core/loader.py", line 49, in eval_code_block
    'input_size': helpers.input_size(context['job']) if 'input_size' in str(code) else 0
  File "tpv/core/helpers.py", line 32, in input_size
    return calculate_dataset_total(job.input_datasets)/GIGABYTES
  File "tpv/core/helpers.py", line 26, in calculate_dataset_total
    return reduce(sum_total, map(get_dataset_size, unique_datasets.values()), 0.0)
  File "tpv/core/helpers.py", line 16, in get_dataset_size
    return float(dataset.file_size)

from https://sentry.galaxyproject.org/share/issue/96123a088f554a8198b300989af27818/

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[mvdbeek]

Turns out we were persisting a null file_size for terminal datasets all over the place, like when failing a dataset or just accidentally while committing other things while the dataset / job was still being handled, not just in the extended metadata case. Inspecting the dirty object in a session is really useful for finding all of these (as well as unnecessary flushes).

[natefoo]

🎉