Fixes for misc. threading problems found by static analysis and helgrind

[dan131riley]

Miscellaneous small fixes to simulation routines found by static analysis and helgrind runs with the multithreaded mixing module. Issues are all harmless, these are all either quieting warnings or improving efficiency.

[cmsbuild]

A new Pull Request was created by @dan131riley (Dan Riley) for CMSSW_8_0_X.

It involves the following packages:

SimCalorimetry/HcalSimAlgos
SimGeneral/DataMixingModule
SimTracker/SiPixelDigitizer
SimTracker/SiStripDigitizer

@cmsbuild, @civanch, @mdhildreth, @davidlange6 can you please review it and eventually sign? Thanks.
@wmtan, @makortel, @GiacomoSguazzoni, @jlagram, @rovere, @VinInn, @cnuttens, @prolay, @dkotlins, @cerati, @threus, @dgulhan, @LBeck this is something you requested to watch as well.
@slava77, @Degano, @smuzaffar you are the release manager for this.

cms-bot commands are list here #13028

[Dr15Jones]

Seems good to me

[Dr15Jones]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/10959/console

[cmsbuild]

+1
Tested at: 2dca225
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-13168/10959/summary.html

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-13168/10959/summary.html

[civanch]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_8_0_X IBs (tests are also fine). This pull request requires discussion in the ORP meeting before it's merged. @slava77, @davidlange6, @Degano, @smuzaffar

[davidlange6]

+1