[JENKINS-26278] Let a combobox display its drop-down when focused.
[JENKINS-26278] Let a combobox display its drop-down when focused.

This pull request integrates https://github.com/jenkinsci/jenkins/pull/1510

gusreiber/jenkins,msrb/jenkins,evernat/jenkins,MichaelPranovich/jenkins_sc,aldaris/jenkins,tfennelly/jenkins,protazy/jenkins,jpbriend/jenkins,azweb76/jenkins,christ66/jenkins,damianszczepanik/jenkins,godfath3r/jenkins,rsandell/jenkins,gusreiber/jenkins,sathiya-mit/jenkins,jpederzolli/jenkins-1,mdonohue/jenkins,msrb/jenkins,wuwen5/jenkins,csimons/jenkins,viqueen/jenkins,olivergondza/jenkins,oleg-nenashev/jenkins,ChrisA89/jenkins,Jimilian/jenkins,Vlatombe/jenkins,dennisjlee/jenkins,fbelzunc/jenkins,amuniz/jenkins,mrooney/jenkins,evernat/jenkins,pjanouse/jenkins,ydubreuil/jenkins,patbos/jenkins,vjuranek/jenkins,Jochen-A-Fuerbacher/jenkins,lilyJi/jenkins,protazy/jenkins,FarmGeek4Life/jenkins,kohsuke/hudson,mdonohue/jenkins,MichaelPranovich/jenkins_sc,amruthsoft9/Jenkis,daniel-beck/jenkins,v1v/jenkins,gusreiber/jenkins,msrb/jenkins,wuwen5/jenkins,SebastienGllmt/jenkins,paulmillar/jenkins,daniel-beck/jenkins,gitaccountforprashant/gittest,Ykus/jenkins,bpzhang/jenkins,paulmillar/jenkins,sathiya-mit/jenkins,jenkinsci/jenkins,escoem/jenkins,rsandell/jenkins,ErikVerheul/jenkins,Jochen-A-Fuerbacher/jenkins,tfennelly/jenkins,azweb76/jenkins,ndeloof/jenkins,Vlatombe/jenkins,batmat/jenkins,christ66/jenkins,pjanouse/jenkins,ikedam/jenkins,samatdav/jenkins,tfennelly/jenkins,ndeloof/jenkins,hplatou/jenkins,damianszczepanik/jenkins,rsandell/jenkins,ChrisA89/jenkins,azweb76/jenkins,duzifang/my-jenkins,rlugojr/jenkins,bkmeneguello/jenkins,ErikVerheul/jenkins,olivergondza/jenkins,mdonohue/jenkins,ErikVerheul/jenkins,damianszczepanik/jenkins,recena/jenkins,MarkEWaite/jenkins,ndeloof/jenkins,MichaelPranovich/jenkins_sc,kzantow/jenkins,varmenise/jenkins,csimons/jenkins,alvarolobato/jenkins,Ykus/jenkins,MarkEWaite/jenkins,batmat/jenkins,escoem/jenkins,protazy/jenkins,mrooney/jenkins,godfath3r/jenkins,msrb/jenkins,tfennelly/jenkins,gitaccountforprashant/gittest,batmat/jenkins,Jochen-A-Fuerbacher/jenkins,bpzhang/jenkins,sathiya-mit/jenkins,jpbriend/jenkins,oleg-nenashev/jenkins,andresrc/jenkins,bkmeneguello/jenkins,ydubreuil/jenkins,dariver/jenkins,alvarolobato/jenkins,andresrc/jenkins,Vlatombe/jenkins,Jochen-A-Fuerbacher/jenkins,paulmillar/jenkins,mdonohue/jenkins,aldaris/jenkins,csimons/jenkins,godfath3r/jenkins,SebastienGllmt/jenkins,lilyJi/jenkins,huybrechts/hudson,ndeloof/jenkins,amuniz/jenkins,damianszczepanik/jenkins,varmenise/jenkins,jpederzolli/jenkins-1,kzantow/jenkins,kohsuke/hudson,duzifang/my-jenkins,samatdav/jenkins,MarkEWaite/jenkins,amuniz/jenkins,escoem/jenkins,rlugojr/jenkins,ajshastri/jenkins,bpzhang/jenkins,azweb76/jenkins,viqueen/jenkins,v1v/jenkins,pjanouse/jenkins,gitaccountforprashant/gittest,duzifang/my-jenkins,NehemiahMi/jenkins,oleg-nenashev/jenkins,christ66/jenkins,christ66/jenkins,amruthsoft9/Jenkis,bpzhang/jenkins,gitaccountforprashant/gittest,huybrechts/hudson,FarmGeek4Life/jenkins,kzantow/jenkins,msrb/jenkins,Jimilian/jenkins,samatdav/jenkins,ndeloof/jenkins,dariver/jenkins,fbelzunc/jenkins,mdonohue/jenkins,wuwen5/jenkins,fbelzunc/jenkins,alvarolobato/jenkins,olivergondza/jenkins,MarkEWaite/jenkins,fbelzunc/jenkins,sathiya-mit/jenkins,msrb/jenkins,varmenise/jenkins,amruthsoft9/Jenkis,jpbriend/jenkins,mrooney/jenkins,kohsuke/hudson,stephenc/jenkins,alvarolobato/jenkins,jpbriend/jenkins,lilyJi/jenkins,ChrisA89/jenkins,paulmillar/jenkins,jpbriend/jenkins,jglick/jenkins,pjanouse/jenkins,damianszczepanik/jenkins,dennisjlee/jenkins,evernat/jenkins,jpbriend/jenkins,dariver/jenkins,mdonohue/jenkins,ajshastri/jenkins,Vlatombe/jenkins,gitaccountforprashant/gittest,andresrc/jenkins,samatdav/jenkins,damianszczepanik/jenkins,duzifang/my-jenkins,christ66/jenkins,patbos/jenkins,gusreiber/jenkins,batmat/jenkins,dennisjlee/jenkins,jpbriend/jenkins,batmat/jenkins,tangkun75/jenkins,bkmeneguello/jenkins,kzantow/jenkins,stephenc/jenkins,protazy/jenkins,vjuranek/jenkins,Jochen-A-Fuerbacher/jenkins,patbos/jenkins,dariver/jenkins,ikedam/jenkins,wuwen5/jenkins,bkmeneguello/jenkins,vjuranek/jenkins,dennisjlee/jenkins,godfath3r/jenkins,NehemiahMi/jenkins,samatdav/jenkins,amuniz/jenkins,MarkEWaite/jenkins,tangkun75/jenkins,Jimilian/jenkins,alvarolobato/jenkins,ndeloof/jenkins,ajshastri/jenkins,huybrechts/hudson,Ykus/jenkins,recena/jenkins,amruthsoft9/Jenkis,tfennelly/jenkins,rsandell/jenkins,bpzhang/jenkins,jpederzolli/jenkins-1,protazy/jenkins,tfennelly/jenkins,Jochen-A-Fuerbacher/jenkins,DanielWeber/jenkins,SebastienGllmt/jenkins,ikedam/jenkins,Jochen-A-Fuerbacher/jenkins,evernat/jenkins,bkmeneguello/jenkins,sathiya-mit/jenkins,recena/jenkins,gusreiber/jenkins,dariver/jenkins,oleg-nenashev/jenkins,hplatou/jenkins,tfennelly/jenkins,duzifang/my-jenkins,Ykus/jenkins,hplatou/jenkins,ndeloof/jenkins,viqueen/jenkins,sathiya-mit/jenkins,pjanouse/jenkins,lilyJi/jenkins,godfath3r/jenkins,daniel-beck/jenkins,alvarolobato/jenkins,pjanouse/jenkins,kohsuke/hudson,paulmillar/jenkins,NehemiahMi/jenkins,daniel-beck/jenkins,bkmeneguello/jenkins,samatdav/jenkins,jenkinsci/jenkins,DanielWeber/jenkins,stephenc/jenkins,jpederzolli/jenkins-1,Ykus/jenkins,viqueen/jenkins,kzantow/jenkins,v1v/jenkins,kohsuke/hudson,christ66/jenkins,MarkEWaite/jenkins,kzantow/jenkins,csimons/jenkins,mrooney/jenkins,oleg-nenashev/jenkins,evernat/jenkins,Vlatombe/jenkins,fbelzunc/jenkins,ydubreuil/jenkins,olivergondza/jenkins,escoem/jenkins,mrooney/jenkins,recena/jenkins,christ66/jenkins,amuniz/jenkins,Jimilian/jenkins,pjanouse/jenkins,v1v/jenkins,mrooney/jenkins,csimons/jenkins,paulmillar/jenkins,varmenise/jenkins,Ykus/jenkins,stephenc/jenkins,ydubreuil/jenkins,jenkinsci/jenkins,ChrisA89/jenkins,godfath3r/jenkins,DanielWeber/jenkins,rsandell/jenkins,Vlatombe/jenkins,vjuranek/jenkins,DanielWeber/jenkins,hplatou/jenkins,viqueen/jenkins,SebastienGllmt/jenkins,amruthsoft9/Jenkis,FarmGeek4Life/jenkins,daniel-beck/jenkins,tangkun75/jenkins,dariver/jenkins,evernat/jenkins,kzantow/jenkins,wuwen5/jenkins,azweb76/jenkins,ajshastri/jenkins,alvarolobato/jenkins,v1v/jenkins,ikedam/jenkins,ikedam/jenkins,jglick/jenkins,viqueen/jenkins,vjuranek/jenkins,paulmillar/jenkins,DanielWeber/jenkins,viqueen/jenkins,jenkinsci/jenkins,stephenc/jenkins,sathiya-mit/jenkins,varmenise/jenkins,bkmeneguello/jenkins,dennisjlee/jenkins,huybrechts/hudson,Jimilian/jenkins,daniel-beck/jenkins,mrooney/jenkins,escoem/jenkins,jglick/jenkins,ikedam/jenkins,dennisjlee/jenkins,tangkun75/jenkins,patbos/jenkins,damianszczepanik/jenkins,ChrisA89/jenkins,jglick/jenkins,amuniz/jenkins,huybrechts/hudson,ErikVerheul/jenkins,recena/jenkins,csimons/jenkins,SebastienGllmt/jenkins,recena/jenkins,varmenise/jenkins,lilyJi/jenkins,patbos/jenkins,andresrc/jenkins,batmat/jenkins,hplatou/jenkins,aldaris/jenkins,lilyJi/jenkins,escoem/jenkins,oleg-nenashev/jenkins,gusreiber/jenkins,jglick/jenkins,huybrechts/hudson,aldaris/jenkins,jglick/jenkins,patbos/jenkins,protazy/jenkins,rsandell/jenkins,amruthsoft9/Jenkis,vjuranek/jenkins,olivergondza/jenkins,hplatou/jenkins,ydubreuil/jenkins,rlugojr/jenkins,fbelzunc/jenkins,dennisjlee/jenkins,aldaris/jenkins,Vlatombe/jenkins,FarmGeek4Life/jenkins,jpederzolli/jenkins-1,rsandell/jenkins,recena/jenkins,evernat/jenkins,DanielWeber/jenkins,vjuranek/jenkins,olivergondza/jenkins,oleg-nenashev/jenkins,tangkun75/jenkins,rsandell/jenkins,tangkun75/jenkins,ErikVerheul/jenkins,daniel-beck/jenkins,v1v/jenkins,jenkinsci/jenkins,escoem/jenkins,v1v/jenkins,FarmGeek4Life/jenkins,Jimilian/jenkins,huybrechts/hudson,dariver/jenkins,NehemiahMi/jenkins,SebastienGllmt/jenkins,aldaris/jenkins,MichaelPranovich/jenkins_sc,patbos/jenkins,jenkinsci/jenkins,ajshastri/jenkins,gusreiber/jenkins,varmenise/jenkins,duzifang/my-jenkins,FarmGeek4Life/jenkins,andresrc/jenkins,kohsuke/hudson,bpzhang/jenkins,tangkun75/jenkins,batmat/jenkins,samatdav/jenkins,msrb/jenkins,csimons/jenkins,MarkEWaite/jenkins,kohsuke/hudson,ydubreuil/jenkins,ChrisA89/jenkins,ErikVerheul/jenkins,rlugojr/jenkins,jenkinsci/jenkins,hplatou/jenkins,kohsuke/hudson,MarkEWaite/jenkins,protazy/jenkins,Jimilian/jenkins,wuwen5/jenkins,DanielWeber/jenkins,gitaccountforprashant/gittest,MichaelPranovich/jenkins_sc,godfath3r/jenkins,stephenc/jenkins,mdonohue/jenkins,bpzhang/jenkins,ikedam/jenkins,amuniz/jenkins,jglick/jenkins,NehemiahMi/jenkins,FarmGeek4Life/jenkins,andresrc/jenkins,Ykus/jenkins,ydubreuil/jenkins,ChrisA89/jenkins,azweb76/jenkins,daniel-beck/jenkins,lilyJi/jenkins,duzifang/my-jenkins,damianszczepanik/jenkins,NehemiahMi/jenkins,jenkinsci/jenkins,azweb76/jenkins,jpederzolli/jenkins-1,gitaccountforprashant/gittest,stephenc/jenkins,MichaelPranovich/jenkins_sc,ikedam/jenkins,rlugojr/jenkins,aldaris/jenkins,ajshastri/jenkins,ajshastri/jenkins,MichaelPranovich/jenkins_sc,rlugojr/jenkins,jpederzolli/jenkins-1,andresrc/jenkins,fbelzunc/jenkins,olivergondza/jenkins,ErikVerheul/jenkins,NehemiahMi/jenkins,amruthsoft9/Jenkis,SebastienGllmt/jenkins,rlugojr/jenkins,wuwen5/jenkins