gcc7 compilation warning(s) fix(es) in ElectroWeakAnalysis/ZMuMu pkg

[mrodozov]

Fix for compilation warning(s) when compiling with gcc7 and more flags listed here:
https://cmssdt.cern.ch/SDT/cgi-bin/buildlogs/slc6_amd64_gcc700/CMSSW_9_3_X_2017-07-24-2300/ElectroWeakAnalysis/ZMuMu

[cmsbuild]

A new Pull Request was created by @mrodozov for master.

It involves the following packages:

ElectroWeakAnalysis/ZMuMu

@cmsbuild, @monttj, @davidlange6 can you please review it and eventually sign? Thanks.
@davidlange6 you are the release manager for this.

cms-bot commands are listed here

[davidlange6]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/21771/console Started: 2017/07/26 09:55

[cmsbuild]

+1
Tested at: 8678429
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-19902/21771/summary.html

The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic:
cc98e01
You can see more details here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-19902/21771/git-log-recent-commits
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-19902/21771/git-merge-result

[cmsbuild]

Comparison job queued.

[davidlange6]

merge

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-19902/21771/summary.html

Comparison Summary:

• You potentially added 5 lines to the logs
• Reco comparison results: 0 differences found in the comparisons
• DQMHistoTests: Total files compared: 23
• DQMHistoTests: Total histograms compared: 2363781
• DQMHistoTests: Total failures: 14625
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 2348990
• DQMHistoTests: Total skipped: 166
• DQMHistoTests: Total Missing objects: 0
• Checked 93 log files, 14 edm output root files, 23 DQM output files