Fix sherpa weights when no weight list is provided

[thuer]

Backport of the fix of sherpaweights (#15733)

[cmsbuild]

A new Pull Request was created by @thuer (Sebastian Thüer) for CMSSW_7_1_X.

It involves the following packages:

GeneratorInterface/SherpaInterface

@cmsbuild, @govoni, @perrozzi, @thuer, @davidlange6 can you please review it and eventually sign? Thanks.
@agrohsje, @mkirsano this is something you requested to watch as well.
@slava77, @smuzaffar you are the release manager for this.

cms-bot commands are list here #13028

[perrozzi]

+1

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/15032/console

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_7_1_X IBs after it passes the integration tests. This pull request requires discussion in the ORP meeting before it's merged. @slava77, @davidlange6, @smuzaffar

[cmsbuild]

-1

Tested at: 0289558

You can see the results of the tests here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-15775/15032/summary.html

I found follow errors while testing this PR

Failed tests: RelVals

• RelVals:

When I ran the RelVals I found an error in the following worklfows:
4.53 step2

runTheMatrix-results/4.53_RunPhoton2012B+RunPhoton2012B+HLTD+RECODreHLT+HARVESTDreHLT/step2_RunPhoton2012B+RunPhoton2012B+HLTD+RECODreHLT+HARVESTDreHLT.log

[thuer]

that error is not related to the pull request.

[thuer]

can we test again?

[perrozzi]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/15065/console

[cmsbuild]

+1
Tested at: 0289558
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-15775/15065/summary.html

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-15775/15065/summary.html

[davidlange6]

+1