Make sure test runner exits, even if the test class threw an exception
Make sure test runner exits, even if the test class threw an exception

Summary:
If a test class fails in a static initialiser then the test runner hangs.
Closes https://github.com/facebook/buck/pull/141

Test Plan: `buck test --all`

dsyang/buck,lukw00/buck,romanoid/buck,raviagarwal7/buck,romanoid/buck,vschs007/buck,janicduplessis/buck,janicduplessis/buck,Distrotech/buck,hgl888/buck,1yvT0s/buck,illicitonion/buck,stuhood/buck,justinmuller/buck,justinmuller/buck,OkBuilds/buck,brettwooldridge/buck,shs96c/buck,mogers/buck,darkforestzero/buck,clonetwin26/buck,grumpyjames/buck,1yvT0s/buck,illicitonion/buck,sdwilsh/buck,OkBuilds/buck,vschs007/buck,grumpyjames/buck,robbertvanginkel/buck,JoelMarcey/buck,bocon13/buck,dpursehouse/buck,justinmuller/buck,mogers/buck,davido/buck,rhencke/buck,vine/buck,SeleniumHQ/buck,Addepar/buck,raviagarwal7/buck,daedric/buck,dsyang/buck,zhuxiaohao/buck,lukw00/buck,sdwilsh/buck,justinmuller/buck,raviagarwal7/buck,daedric/buck,dushmis/buck,neonichu/buck,k21/buck,k21/buck,facebook/buck,shybovycha/buck,shybovycha/buck,MarkRunWu/buck,nguyentruongtho/buck,rowillia/buck,OkBuilds/buck,janicduplessis/buck,Dominator008/buck,mogers/buck,LegNeato/buck,siddhartharay007/buck,zhuxiaohao/buck,raviagarwal7/buck,saleeh93/buck-cutom,OkBuilds/buck,pwz3n0/buck,MarkRunWu/buck,illicitonion/buck,bocon13/buck,mread/buck,shybovycha/buck,janicduplessis/buck,justinmuller/buck,davido/buck,dpursehouse/buck,shs96c/buck,Learn-Android-app/buck,zhuxiaohao/buck,Heart2009/buck,marcinkwiatkowski/buck,OkBuilds/buck,luiseduardohdbackup/buck,grumpyjames/buck,OkBuilds/buck,stuhood/buck,saleeh93/buck-cutom,luiseduardohdbackup/buck,rmaz/buck,stuhood/buck,lukw00/buck,SeleniumHQ/buck,mikekap/buck,k21/buck,ilya-klyuchnikov/buck,daedric/buck,mnuessler/buck,ilya-klyuchnikov/buck,JoelMarcey/buck,vschs007/buck,mikekap/buck,Learn-Android-app/buck,daedric/buck,romanoid/buck,darkforestzero/buck,JoelMarcey/buck,zhan-xiong/buck,marcinkwiatkowski/buck,rmaz/buck,raviagarwal7/buck,romanoid/buck,lukw00/buck,raviagarwal7/buck,mread/buck,facebook/buck,siddhartharay007/buck,stuhood/buck,dsyang/buck,LegNeato/buck,rowillia/buck,mnuessler/buck,illicitonion/buck,vschs007/buck,Addepar/buck,dushmis/buck,shs96c/buck,saleeh93/buck-cutom,Addepar/buck,MarkRunWu/buck,robbertvanginkel/buck,dushmis/buck,mogers/buck,dushmis/buck,vine/buck,justinmuller/buck,tgummerer/buck,rhencke/buck,Addepar/buck,JoelMarcey/buck,artiya4u/buck,grumpyjames/buck,ilya-klyuchnikov/buck,JoelMarcey/buck,facebook/buck,grumpyjames/buck,rowillia/buck,justinmuller/buck,davido/buck,dsyang/buck,ilya-klyuchnikov/buck,k21/buck,hgl888/buck,mnuessler/buck,vschs007/buck,ilya-klyuchnikov/buck,daedric/buck,nguyentruongtho/buck,ilya-klyuchnikov/buck,zhuxiaohao/buck,Distrotech/buck,shs96c/buck,siddhartharay007/buck,illicitonion/buck,ilya-klyuchnikov/buck,darkforestzero/buck,OkBuilds/buck,artiya4u/buck,liuyang-li/buck,vine/buck,zhuxiaohao/buck,liuyang-li/buck,kageiit/buck,bocon13/buck,sdwilsh/buck,Addepar/buck,luiseduardohdbackup/buck,siddhartharay007/buck,brettwooldridge/buck,dsyang/buck,raviagarwal7/buck,clonetwin26/buck,1yvT0s/buck,rmaz/buck,rowillia/buck,Distrotech/buck,zhan-xiong/buck,rmaz/buck,JoelMarcey/buck,dushmis/buck,SeleniumHQ/buck,clonetwin26/buck,mogers/buck,marcinkwiatkowski/buck,clonetwin26/buck,dpursehouse/buck,dushmis/buck,sdwilsh/buck,vine/buck,shybovycha/buck,shybovycha/buck,Dominator008/buck,Learn-Android-app/buck,tgummerer/buck,Distrotech/buck,janicduplessis/buck,Addepar/buck,vschs007/buck,zhan-xiong/buck,romanoid/buck,bocon13/buck,vschs007/buck,nguyentruongtho/buck,Dominator008/buck,k21/buck,zhan-xiong/buck,mnuessler/buck,marcinkwiatkowski/buck,1yvT0s/buck,JoelMarcey/buck,kageiit/buck,vine/buck,LegNeato/buck,rmaz/buck,lukw00/buck,Learn-Android-app/buck,rhencke/buck,shybovycha/buck,clonetwin26/buck,vschs007/buck,brettwooldridge/buck,neonichu/buck,zhan-xiong/buck,brettwooldridge/buck,shybovycha/buck,1yvT0s/buck,SeleniumHQ/buck,Learn-Android-app/buck,janicduplessis/buck,dsyang/buck,LegNeato/buck,illicitonion/buck,tgummerer/buck,OkBuilds/buck,MarkRunWu/buck,darkforestzero/buck,luiseduardohdbackup/buck,mikekap/buck,mread/buck,vine/buck,marcinkwiatkowski/buck,brettwooldridge/buck,JoelMarcey/buck,davido/buck,dsyang/buck,shs96c/buck,raviagarwal7/buck,MarkRunWu/buck,saleeh93/buck-cutom,marcinkwiatkowski/buck,SeleniumHQ/buck,mogers/buck,Distrotech/buck,nguyentruongtho/buck,neonichu/buck,Learn-Android-app/buck,shs96c/buck,Addepar/buck,vine/buck,grumpyjames/buck,bocon13/buck,janicduplessis/buck,hgl888/buck,rmaz/buck,marcinkwiatkowski/buck,davido/buck,dpursehouse/buck,grumpyjames/buck,davido/buck,luiseduardohdbackup/buck,clonetwin26/buck,Heart2009/buck,bocon13/buck,brettwooldridge/buck,davido/buck,mread/buck,saleeh93/buck-cutom,dushmis/buck,Dominator008/buck,clonetwin26/buck,marcinkwiatkowski/buck,neonichu/buck,darkforestzero/buck,sdwilsh/buck,romanoid/buck,grumpyjames/buck,dushmis/buck,LegNeato/buck,illicitonion/buck,stuhood/buck,Heart2009/buck,Dominator008/buck,k21/buck,stuhood/buck,liuyang-li/buck,lukw00/buck,janicduplessis/buck,Learn-Android-app/buck,grumpyjames/buck,artiya4u/buck,1yvT0s/buck,shybovycha/buck,darkforestzero/buck,mikekap/buck,zhuxiaohao/buck,kageiit/buck,Distrotech/buck,artiya4u/buck,kageiit/buck,Dominator008/buck,liuyang-li/buck,artiya4u/buck,grumpyjames/buck,Dominator008/buck,tgummerer/buck,romanoid/buck,robbertvanginkel/buck,nguyentruongtho/buck,1yvT0s/buck,dsyang/buck,Dominator008/buck,OkBuilds/buck,robbertvanginkel/buck,shs96c/buck,zhuxiaohao/buck,OkBuilds/buck,brettwooldridge/buck,raviagarwal7/buck,facebook/buck,zhan-xiong/buck,zhan-xiong/buck,Learn-Android-app/buck,shs96c/buck,clonetwin26/buck,siddhartharay007/buck,hgl888/buck,LegNeato/buck,liuyang-li/buck,SeleniumHQ/buck,dpursehouse/buck,SeleniumHQ/buck,LegNeato/buck,illicitonion/buck,artiya4u/buck,grumpyjames/buck,rowillia/buck,artiya4u/buck,shs96c/buck,robbertvanginkel/buck,mogers/buck,Heart2009/buck,darkforestzero/buck,zpao/buck,liuyang-li/buck,shs96c/buck,Dominator008/buck,luiseduardohdbackup/buck,pwz3n0/buck,daedric/buck,davido/buck,robbertvanginkel/buck,bocon13/buck,pwz3n0/buck,sdwilsh/buck,grumpyjames/buck,marcinkwiatkowski/buck,1yvT0s/buck,dpursehouse/buck,clonetwin26/buck,daedric/buck,mnuessler/buck,LegNeato/buck,pwz3n0/buck,bocon13/buck,vine/buck,rowillia/buck,liuyang-li/buck,ilya-klyuchnikov/buck,nguyentruongtho/buck,mikekap/buck,mogers/buck,MarkRunWu/buck,illicitonion/buck,dsyang/buck,Learn-Android-app/buck,dsyang/buck,kageiit/buck,mikekap/buck,mikekap/buck,vschs007/buck,vschs007/buck,shs96c/buck,k21/buck,daedric/buck,rhencke/buck,pwz3n0/buck,Addepar/buck,facebook/buck,robbertvanginkel/buck,lukw00/buck,dushmis/buck,dpursehouse/buck,justinmuller/buck,romanoid/buck,marcinkwiatkowski/buck,brettwooldridge/buck,hgl888/buck,vine/buck,rowillia/buck,Heart2009/buck,Distrotech/buck,zhuxiaohao/buck,justinmuller/buck,liuyang-li/buck,davido/buck,mogers/buck,mnuessler/buck,sdwilsh/buck,marcinkwiatkowski/buck,davido/buck,robbertvanginkel/buck,luiseduardohdbackup/buck,siddhartharay007/buck,tgummerer/buck,mikekap/buck,liuyang-li/buck,luiseduardohdbackup/buck,shs96c/buck,SeleniumHQ/buck,mogers/buck,zpao/buck,dpursehouse/buck,LegNeato/buck,JoelMarcey/buck,k21/buck,luiseduardohdbackup/buck,neonichu/buck,janicduplessis/buck,mikekap/buck,mnuessler/buck,Learn-Android-app/buck,clonetwin26/buck,daedric/buck,zhan-xiong/buck,rmaz/buck,mikekap/buck,dsyang/buck,rowillia/buck,rowillia/buck,rhencke/buck,artiya4u/buck,mnuessler/buck,pwz3n0/buck,bocon13/buck,rhencke/buck,stuhood/buck,rmaz/buck,zhan-xiong/buck,robbertvanginkel/buck,k21/buck,romanoid/buck,raviagarwal7/buck,davido/buck,Addepar/buck,Heart2009/buck,saleeh93/buck-cutom,lukw00/buck,rhencke/buck,zhan-xiong/buck,artiya4u/buck,facebook/buck,k21/buck,shybovycha/buck,LegNeato/buck,brettwooldridge/buck,Heart2009/buck,zhan-xiong/buck,ilya-klyuchnikov/buck,JoelMarcey/buck,rhencke/buck,illicitonion/buck,robbertvanginkel/buck,siddhartharay007/buck,darkforestzero/buck,janicduplessis/buck,darkforestzero/buck,marcinkwiatkowski/buck,sdwilsh/buck,zpao/buck,darkforestzero/buck,davido/buck,daedric/buck,tgummerer/buck,justinmuller/buck,lukw00/buck,shybovycha/buck,romanoid/buck,darkforestzero/buck,raviagarwal7/buck,bocon13/buck,LegNeato/buck,Dominator008/buck,daedric/buck,SeleniumHQ/buck,bocon13/buck,vine/buck,k21/buck,robbertvanginkel/buck,SeleniumHQ/buck,dsyang/buck,sdwilsh/buck,romanoid/buck,zpao/buck,rowillia/buck,stuhood/buck,zhuxiaohao/buck,LegNeato/buck,darkforestzero/buck,sdwilsh/buck,Distrotech/buck,siddhartharay007/buck,raviagarwal7/buck,tgummerer/buck,liuyang-li/buck,SeleniumHQ/buck,vschs007/buck,mogers/buck,artiya4u/buck,marcinkwiatkowski/buck,Dominator008/buck,hgl888/buck,Distrotech/buck,vschs007/buck,facebook/buck,Distrotech/buck,Learn-Android-app/buck,artiya4u/buck,justinmuller/buck,hgl888/buck,zpao/buck,janicduplessis/buck,SeleniumHQ/buck,Addepar/buck,sdwilsh/buck,rhencke/buck,JoelMarcey/buck,dushmis/buck,tgummerer/buck,Addepar/buck,kageiit/buck,SeleniumHQ/buck,ilya-klyuchnikov/buck,liuyang-li/buck,pwz3n0/buck,MarkRunWu/buck,davido/buck,Dominator008/buck,shybovycha/buck,JoelMarcey/buck,justinmuller/buck,LegNeato/buck,ilya-klyuchnikov/buck,ilya-klyuchnikov/buck,shybovycha/buck,neonichu/buck,rowillia/buck,romanoid/buck,brettwooldridge/buck,pwz3n0/buck,kageiit/buck,hgl888/buck,neonichu/buck,raviagarwal7/buck,stuhood/buck,brettwooldridge/buck,Distrotech/buck,1yvT0s/buck,janicduplessis/buck,illicitonion/buck,rmaz/buck,hgl888/buck,mikekap/buck,zpao/buck,illicitonion/buck,sdwilsh/buck,rmaz/buck,mread/buck,daedric/buck,pwz3n0/buck,clonetwin26/buck,lukw00/buck,tgummerer/buck,rhencke/buck,robbertvanginkel/buck,ilya-klyuchnikov/buck,lukw00/buck,zpao/buck,stuhood/buck,rhencke/buck,illicitonion/buck,clonetwin26/buck,mnuessler/buck,pwz3n0/buck,vschs007/buck,zhan-xiong/buck,JoelMarcey/buck,nguyentruongtho/buck,zhan-xiong/buck,shybovycha/buck,vine/buck,mread/buck,mikekap/buck,justinmuller/buck,clonetwin26/buck,tgummerer/buck,sdwilsh/buck,brettwooldridge/buck,daedric/buck,bocon13/buck,k21/buck,pwz3n0/buck,neonichu/buck,Addepar/buck,MarkRunWu/buck,rmaz/buck,Addepar/buck,Heart2009/buck,OkBuilds/buck,Heart2009/buck,dsyang/buck,brettwooldridge/buck,rowillia/buck,romanoid/buck,shs96c/buck,stuhood/buck,siddhartharay007/buck,robbertvanginkel/buck,OkBuilds/buck,tgummerer/buck,k21/buck,rmaz/buck,darkforestzero/buck,rmaz/buck,OkBuilds/buck,neonichu/buck