[10.6.X] cherry pick root-project/root#3485

[smuzaffar]

Set offset of the used-for-write element in case of I/O rule on 'current' StreamerInfo.

This fixes ROOT-10016

[smuzaffar]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/33440/console
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/33441/console

[cmsbuild]

A new Pull Request was created by @smuzaffar (Malik Shahzad Muzaffar) for branch IB/CMSSW_10_6_X/gcc700.

@cmsbuild, @smuzaffar, @gudrutis, @mrodozov can you please review it and eventually sign? Thanks.
You can sign-off by replying to this message having '+1' in the first line of your reply.
You can reject by replying to this message having '-1' in the first line of your reply.

[cmsbuild]

-1

Tested at: e9b4264

You can see the results of the tests here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-4757/33441/summary.html

I found follow errors while testing this PR

Failed tests: UnitTests

• Unit Tests:

I found errors in the following unit tests:

---> test ExpressionEvaluatorUnitTest had ERRORS

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-4757/33441/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 5 differences found in the comparisons
• DQMHistoTests: Total files compared: 32
• DQMHistoTests: Total histograms compared: 3114826
• DQMHistoTests: Total failures: 1
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3114628
• DQMHistoTests: Total skipped: 197
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 31 files compared)
• Checked 133 log files, 14 edm output root files, 32 DQM output files

[smuzaffar]

+externals
unit test is known to fail (hang)

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next IB/CMSSW_10_6_X/gcc700 IBs (but tests are reportedly failing). 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)