Use TTreeCache for RootEmbeddedFileSequence

[dan131riley]

This modifies RootEmbeddedFileSequence to have basically the same settings for the ROOT TTreeCache as the primary input file, defaulting to having the cache on. RootEmbeddedFileSequence is only used by the MixingModule, so this change will turn on caching for the MixingModule inputs without affecting any other use cases.

[cmsbuild]

A new Pull Request was created by @dan131riley (Dan Riley) for CMSSW_8_1_X.

It involves the following packages:

IOPool/Input

@cmsbuild, @smuzaffar, @Dr15Jones, @davidlange6 can you please review it and eventually sign? Thanks.
@wddgit, @wmtan 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

[Dr15Jones]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/15526/console

[cmsbuild]

+1
Tested at: b142aa2
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-16091/15526/summary.html

[Dr15Jones]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_8_1_X IBs (tests are also fine). This pull request requires discussion in the ORP meeting before it's merged. @slava77, @davidlange6, @smuzaffar

[Dr15Jones]

@bbockelm any suggestions on how to further test this change?

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-16091/15526/summary.html

[davidlange6]

+1