Fix packed gen particle copy and move ctors

[wmtan]

Pr #11706 created explicit copy and move constructors for pat::PackedGenParticle.
Unfortunately, the packed quantities were left out, so they were neither moved nor copied.
This PR fixes that, and also enhances the unit test so that this would have been caught.
This fixes the discrepancy recently seen in PackedGenParticle.

[wmtan]

@cmsbuild please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/9076/console

[cmsbuild]

A new Pull Request was created by @wmtan for CMSSW_7_6_X.

Fix packed gen particle copy and move ctors

It involves the following packages:

DataFormats/PatCandidates

@cmsbuild, @vadler, @monttj can you please review it and eventually sign? Thanks.
@gpetruc 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]

What about the operator=?

[wmtan]

@Dr15Jones OK, I need to fix operator(s) = also.

[wmtan]

@Dr15Jones @davidlange6 I updated this PR both to fix the assignment operators and to use the
CMS_THREAD_GUARD macro to avoid the build warnings.

[wmtan]

@cmsbuild please test

[cmsbuild]

+1
Tested at: bff3e7d
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-12000/9076/summary.html

[cmsbuild]

Pull request #12000 was updated. @vadler, @monttj can you please check and sign again.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-12000/9076/summary.html

[Dr15Jones]

@vadler, @monttj @davidlange6 this is critical for fixing a bug already in the release