Fix _ModuleSequenceType.insert() when it is empty or contains only Tasks

[makortel]

Following the same pattern as in __imul__ and __iadd__.

Tested in 10_4_0_pre1, no changes expected.

[cmsbuild]

The code-checks are being triggered in jenkins.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-25079/7074

[cmsbuild]

A new Pull Request was created by @makortel (Matti Kortelainen) for master.

It involves the following packages:

FWCore/ParameterSet

@cmsbuild, @smuzaffar, @Dr15Jones can you please review it and eventually sign? Thanks.
@Martin-Grunewald, @wddgit this is something you requested to watch as well.
@davidlange6, @slava77, @fabiocos you are the release manager for this.

cms-bot commands are listed here

[makortel]

@cmsbuild, please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/31410/console Started: 2018/10/31 22:16

[cmsbuild]

+1
Tested at: 1f47b1c
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-25079/31410/summary.html

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-25079/31410/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 0 differences found in the comparisons
• DQMHistoTests: Total files compared: 32
• DQMHistoTests: Total histograms compared: 2994773
• DQMHistoTests: Total failures: 1
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 2994575
• DQMHistoTests: Total skipped: 197
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 31 files compared)
• Checked 134 log files, 14 edm output root files, 32 DQM output files

[Dr15Jones]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next master IBs (tests are also fine). This pull request will now be reviewed by the release team before it's merged. @davidlange6, @slava77, @smuzaffar, @fabiocos (and backports should be raised in the release meeting by the corresponding L2)

[fabiocos]

+1