Fix bug that caused daughters of particle with index 0 to not be assigned any mother
Merge branch 'CMSSW_7_2_X' of https://github.com/cms-sw/cmssw into GenParticlePrunerBugFix
Merge pull request #5008 from wulsin/GenParticlePrunerBugFix

Gen particle pruner bug fix
Merge remote branch 'origin/CMSSW_7_2_X' into CMSSW_7_0_X