add missing initializations in pat::Muon (minimal catch up to #28212 and #29324)

[slava77]

some missing initializations were discovered during backport of #28212 to 10_6_X, as done in #29324. This PR fixes the master part.

[cmsbuild]

The code-checks are being triggered in jenkins.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-29432/14595

• This PR adds an extra 16KB to repository

[cmsbuild]

A new Pull Request was created by @slava77 (Slava Krutelyov) for master.

It involves the following packages:

DataFormats/PatCandidates

@perrotta, @cmsbuild, @santocch, @slava77 can you please review it and eventually sign? Thanks.
@gouskos, @hatakeyamak, @rovere, @cbernet, @gpetruc, @peruzzim this is something you requested to watch as well.
@silviodonato, @dpiparo you are the release manager for this.

cms-bot commands are listed here

[slava77]

@cmsbuild please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-run-pr-tests/5613/console Started: 2020/04/08 23:40

[cmsbuild]

+1
Tested at: 8210d10
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-f26982/5613/summary.html
CMSSW: CMSSW_11_1_X_2020-04-08-1100
SCRAM_ARCH: slc7_amd64_gcc820

The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic:

• Running code-format for dqm #29424 @cms-sw: Running code-format for dqm

You can see more details here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-f26982/5613/git-log-recent-commits
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-f26982/5613/git-merge-result

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-f26982/5613/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 4 differences found in the comparisons
• DQMHistoTests: Total files compared: 34
• DQMHistoTests: Total histograms compared: 2692110
• DQMHistoTests: Total failures: 8
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 2691783
• DQMHistoTests: Total skipped: 319
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 33 files compared)
• Checked 147 log files, 16 edm output root files, 34 DQM output files

[slava77]

+1

for #29432 8210d10

• technical

[santocch]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next master IBs (tests are also fine). This pull request will now be reviewed by the release team before it's merged. @silviodonato, @dpiparo (and backports should be raised in the release meeting by the corresponding L2)

[silviodonato]

+1