Bug fix. Add function to get top level PSet

[wddgit]

Add a new function that allows one to get a
top level ParameterSet by passing in a
ModuleDescription which is available in
all modules.

This is the Core part of the changes needed to
fix modules that were using the old
getProcessParameterSet function. This depends
on a single global static ParameterSetID.
It fails when used in SubProcesses would return
the ParameterSet for the wrong process/SubProcess.
The bug only affects jobs with SubProcesses.
This global was also problematic for multithreading
(had to be protected with a mutex).

More changes will follow this to convert
all uses of the old function to an alternative
and then eventually to delete it. Merging this
PR quickly will make it easier to test the others
quickly.

[cmsbuild]

A new Pull Request was created by @wddgit (W. David Dagenhart) for CMSSW_7_5_X.

Bug fix. Add function to get top level PSet

It involves the following packages:

FWCore/Framework
FWCore/Integration
FWCore/ParameterSet

@cmsbuild, @Dr15Jones can you please review it and eventually sign? Thanks.
@Martin-Grunewald, @wmtan this is something you requested to watch as well.
You can sign-off by replying to this message having '+1' in the first line of your reply.
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@Degano you are the release manager for this.
You can merge this pull request by typing 'merge' in the first line of your comment.

[Dr15Jones]

Please test

[cmsbuild]

The tests are being triggered in jenkins.

[Dr15Jones]

+1

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-9662/2605/summary.html

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_7_5_X IBs (tests are also fine). This pull request requires discussion in the ORP meeting before it's merged. @davidlange6, @Degano, @smuzaffar

[davidlange6]

+1