Fix potential mod by 0 in DecimalValue.
Fix potential mod by 0 in DecimalValue.

This can happen in the case where there is also overflow, in which case
we might take the mod of an uninitialized value. If that value is 0, we
trap.

Change-Id: I0f455de8405512e841d518330ff1e985b225b954
Reviewed-on: http://gerrit.sjc.cloudera.com:8080/5392
Reviewed-by: Nong Li <99a5e5f8f5911755b88e0b536d46aafa102bed41@cloudera.com>
Tested-by: jenkins

brightchen/Impala,bowlofstew/Impala,lnliuxing/Impala,tempbottle/Impala,theyaa/Impala,lirui-intel/Impala,tempbottle/Impala,henryr/Impala,kapilrastogi/Impala,scalingdata/Impala,kapilrastogi/Impala,caseyching/Impala,cloudera/recordservice,kapilrastogi/Impala,henryr/Impala,ImpalaToGo/ImpalaToGo,gerashegalov/Impala,bowlofstew/Impala,cgvarela/Impala,XiaominZhang/Impala,caseyching/Impala,cloudera/recordservice,rdblue/Impala,lirui-intel/Impala,theyaa/Impala,rdblue/Impala,gerashegalov/Impala,brightchen/Impala,ImpalaToGo/ImpalaToGo,theyaa/Impala,XiaominZhang/Impala,bratatidas9/Impala-1,XiaominZhang/Impala,cchanning/Impala,cgvarela/Impala,bowlofstew/Impala,placrosse/ImpalaToGo,scalingdata/Impala,cgvarela/Impala,tempbottle/Impala,lnliuxing/Impala,theyaa/Impala,grundprinzip/Impala,henryr/Impala,ImpalaToGo/ImpalaToGo,kapilrastogi/Impala,caseyching/Impala,rdblue/Impala,kapilrastogi/Impala,gerashegalov/Impala,scalingdata/Impala,brightchen/Impala,cloudera/recordservice,placrosse/ImpalaToGo,cloudera/recordservice,rdblue/Impala,ImpalaToGo/ImpalaToGo,rdblue/Impala,henryr/Impala,cgvarela/Impala,XiaominZhang/Impala,scalingdata/Impala,grundprinzip/Impala,lirui-intel/Impala,scalingdata/Impala,bowlofstew/Impala,theyaa/Impala,caseyching/Impala,brightchen/Impala,henryr/Impala,lnliuxing/Impala,kapilrastogi/Impala,cloudera/recordservice,tempbottle/Impala,placrosse/ImpalaToGo,grundprinzip/Impala,rdblue/Impala,bratatidas9/Impala-1,gerashegalov/Impala,brightchen/Impala,bowlofstew/Impala,placrosse/ImpalaToGo,placrosse/ImpalaToGo,XiaominZhang/Impala,cchanning/Impala,lnliuxing/Impala,tempbottle/Impala,bratatidas9/Impala-1,cloudera/recordservice,henryr/Impala,cgvarela/Impala,ImpalaToGo/ImpalaToGo,bowlofstew/Impala,cchanning/Impala,theyaa/Impala,cchanning/Impala,caseyching/Impala,caseyching/Impala,ImpalaToGo/ImpalaToGo,cchanning/Impala,lirui-intel/Impala,lnliuxing/Impala,bratatidas9/Impala-1,gerashegalov/Impala,kapilrastogi/Impala,gerashegalov/Impala,bratatidas9/Impala-1,rdblue/Impala,brightchen/Impala,bowlofstew/Impala,cgvarela/Impala,cchanning/Impala,cchanning/Impala,tempbottle/Impala,grundprinzip/Impala,theyaa/Impala,lnliuxing/Impala,placrosse/ImpalaToGo,XiaominZhang/Impala,bratatidas9/Impala-1,caseyching/Impala,lnliuxing/Impala,brightchen/Impala,bratatidas9/Impala-1,gerashegalov/Impala,lirui-intel/Impala,lirui-intel/Impala,lirui-intel/Impala,grundprinzip/Impala,cgvarela/Impala,cloudera/recordservice,grundprinzip/Impala,XiaominZhang/Impala,tempbottle/Impala,scalingdata/Impala