IMPALA-932: evaluate concat/concat_ws children once
IMPALA-932: evaluate concat/concat_ws children once

Change-Id: Id22a6c1dfb57cf659a1e24af4de6e5a2336cafa4
Reviewed-on: http://gerrit.ent.cloudera.com:8080/2152
Reviewed-by: Skye Wanderman-Milne <6d4b168ab637b0a20cc9dbf96abb2537f372f946@cloudera.com>
Tested-by: jenkins
(cherry picked from commit cf6960017d4f7d75c1c685cf362bd3d9cd9b63c7)
Reviewed-on: http://gerrit.ent.cloudera.com:8080/2183

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