Ensure EventListenerGuard in every partition
Ensure EventListenerGuard in every partition

EventListenerGuard is a necessary protection from [CoreFX bug 3793](https://github.com/dotnet/corefx/issues/3793).  When partitioning up assemblies we need to ensure that this type is present in every test partition.

closes #10680

CyrusNajmabadi/roslyn,xoofx/roslyn,bkoelman/roslyn,lorcanmooney/roslyn,sharadagrawal/Roslyn,Shiney/roslyn,KiloBravoLima/roslyn,abock/roslyn,Pvlerick/roslyn,swaroop-sridhar/roslyn,Hosch250/roslyn,xoofx/roslyn,a-ctor/roslyn,mavasani/roslyn,natgla/roslyn,mavasani/roslyn,AmadeusW/roslyn,jhendrixMSFT/roslyn,VSadov/roslyn,jkotas/roslyn,mmitche/roslyn,basoundr/roslyn,sharwell/roslyn,yeaicc/roslyn,eriawan/roslyn,Pvlerick/roslyn,paulvanbrenk/roslyn,robinsedlaczek/roslyn,mattscheffer/roslyn,xoofx/roslyn,khyperia/roslyn,khyperia/roslyn,AnthonyDGreen/roslyn,genlu/roslyn,heejaechang/roslyn,srivatsn/roslyn,jeffanders/roslyn,jasonmalinowski/roslyn,jhendrixMSFT/roslyn,OmarTawfik/roslyn,tmeschter/roslyn,KevinRansom/roslyn,diryboy/roslyn,sharadagrawal/Roslyn,amcasey/roslyn,tvand7093/roslyn,jmarolf/roslyn,AnthonyDGreen/roslyn,AdamSpeight2008/roslyn-AdamSpeight2008,AmadeusW/roslyn,srivatsn/roslyn,khellang/roslyn,shyamnamboodiripad/roslyn,mattwar/roslyn,KevinH-MS/roslyn,AArnott/roslyn,AlekseyTs/roslyn,Giftednewt/roslyn,Giftednewt/roslyn,panopticoncentral/roslyn,leppie/roslyn,CyrusNajmabadi/roslyn,AdamSpeight2008/roslyn-AdamSpeight2008,jaredpar/roslyn,brettfo/roslyn,shyamnamboodiripad/roslyn,srivatsn/roslyn,AlekseyTs/roslyn,KevinH-MS/roslyn,zooba/roslyn,tmat/roslyn,panopticoncentral/roslyn,jeffanders/roslyn,bbarry/roslyn,abock/roslyn,drognanar/roslyn,AlekseyTs/roslyn,jcouv/roslyn,VSadov/roslyn,OmarTawfik/roslyn,aelij/roslyn,budcribar/roslyn,genlu/roslyn,dpoeschl/roslyn,jcouv/roslyn,aelij/roslyn,Hosch250/roslyn,pdelvo/roslyn,bartdesmet/roslyn,dotnet/roslyn,sharwell/roslyn,rgani/roslyn,budcribar/roslyn,michalhosala/roslyn,rgani/roslyn,nguerrera/roslyn,jamesqo/roslyn,ErikSchierboom/roslyn,jasonmalinowski/roslyn,jkotas/roslyn,tmeschter/roslyn,davkean/roslyn,MatthieuMEZIL/roslyn,leppie/roslyn,dotnet/roslyn,abock/roslyn,jamesqo/roslyn,balajikris/roslyn,weltkante/roslyn,xasx/roslyn,michalhosala/roslyn,mmitche/roslyn,bkoelman/roslyn,leppie/roslyn,cston/roslyn,heejaechang/roslyn,lorcanmooney/roslyn,natidea/roslyn,aelij/roslyn,KevinRansom/roslyn,MatthieuMEZIL/roslyn,KiloBravoLima/roslyn,reaction1989/roslyn,Hosch250/roslyn,CyrusNajmabadi/roslyn,sharadagrawal/Roslyn,agocke/roslyn,MichalStrehovsky/roslyn,gafter/roslyn,natidea/roslyn,balajikris/roslyn,mavasani/roslyn,vslsnap/roslyn,nguerrera/roslyn,MattWindsor91/roslyn,amcasey/roslyn,swaroop-sridhar/roslyn,bbarry/roslyn,jkotas/roslyn,KevinRansom/roslyn,jcouv/roslyn,Shiney/roslyn,DustinCampbell/roslyn,brettfo/roslyn,OmarTawfik/roslyn,KevinH-MS/roslyn,kelltrick/roslyn,lorcanmooney/roslyn,mmitche/roslyn,tannergooding/roslyn,gafter/roslyn,DustinCampbell/roslyn,robinsedlaczek/roslyn,a-ctor/roslyn,heejaechang/roslyn,drognanar/roslyn,swaroop-sridhar/roslyn,tvand7093/roslyn,reaction1989/roslyn,TyOverby/roslyn,amcasey/roslyn,Shiney/roslyn,jmarolf/roslyn,kelltrick/roslyn,budcribar/roslyn,tannergooding/roslyn,wvdd007/roslyn,paulvanbrenk/roslyn,wvdd007/roslyn,KirillOsenkov/roslyn,zooba/roslyn,eriawan/roslyn,AnthonyDGreen/roslyn,brettfo/roslyn,xasx/roslyn,a-ctor/roslyn,physhi/roslyn,natgla/roslyn,cston/roslyn,khellang/roslyn,MichalStrehovsky/roslyn,jhendrixMSFT/roslyn,yeaicc/roslyn,shyamnamboodiripad/roslyn,pdelvo/roslyn,MattWindsor91/roslyn,mgoertz-msft/roslyn,dotnet/roslyn,tannergooding/roslyn,wvdd007/roslyn,paulvanbrenk/roslyn,ErikSchierboom/roslyn,eriawan/roslyn,ericfe-ms/roslyn,Giftednewt/roslyn,mgoertz-msft/roslyn,akrisiun/roslyn,genlu/roslyn,MattWindsor91/roslyn,xasx/roslyn,natidea/roslyn,orthoxerox/roslyn,KirillOsenkov/roslyn,AdamSpeight2008/roslyn-AdamSpeight2008,jaredpar/roslyn,mgoertz-msft/roslyn,tmeschter/roslyn,basoundr/roslyn,mattscheffer/roslyn,pdelvo/roslyn,orthoxerox/roslyn,panopticoncentral/roslyn,CaptainHayashi/roslyn,tmat/roslyn,MichalStrehovsky/roslyn,VSadov/roslyn,balajikris/roslyn,DustinCampbell/roslyn,ljw1004/roslyn,MatthieuMEZIL/roslyn,jaredpar/roslyn,jasonmalinowski/roslyn,nguerrera/roslyn,dpoeschl/roslyn,vslsnap/roslyn,khellang/roslyn,weltkante/roslyn,mattwar/roslyn,agocke/roslyn,orthoxerox/roslyn,ericfe-ms/roslyn,bkoelman/roslyn,physhi/roslyn,drognanar/roslyn,bartdesmet/roslyn,tvand7093/roslyn,cston/roslyn,akrisiun/roslyn,mattscheffer/roslyn,agocke/roslyn,basoundr/roslyn,michalhosala/roslyn,rgani/roslyn,TyOverby/roslyn,davkean/roslyn,natgla/roslyn,TyOverby/roslyn,ericfe-ms/roslyn,stephentoub/roslyn,ErikSchierboom/roslyn,dpoeschl/roslyn,vslsnap/roslyn,tmat/roslyn,ljw1004/roslyn,AArnott/roslyn,reaction1989/roslyn,robinsedlaczek/roslyn,yeaicc/roslyn,mattwar/roslyn,jamesqo/roslyn,jeffanders/roslyn,diryboy/roslyn,AArnott/roslyn,stephentoub/roslyn,kelltrick/roslyn,AmadeusW/roslyn,KiloBravoLima/roslyn,Pvlerick/roslyn,MattWindsor91/roslyn,sharwell/roslyn,CaptainHayashi/roslyn,ljw1004/roslyn,physhi/roslyn,CaptainHayashi/roslyn,zooba/roslyn,davkean/roslyn,diryboy/roslyn,KirillOsenkov/roslyn,stephentoub/roslyn,jmarolf/roslyn,gafter/roslyn,bbarry/roslyn,khyperia/roslyn,akrisiun/roslyn,weltkante/roslyn,bartdesmet/roslyn