Add a timing test for iterating.  Suggested by http://code.google.com/p/google-sparsehash/issues/detail?id=77
Add a timing test for iterating.  Suggested by
http://code.google.com/p/google-sparsehash/issues/detail?id=77

R=gpike
DELTA=26  (26 added, 0 deleted, 0 changed)


Revision created by MOE tool push_codebase.
MOE_MIGRATION=3519

RChehowski/sparsehash,dabbertorres/GoogleHashMaps,liuqiang2/sparsehash,guiquanz/sparsehash,kinjalbhavsar/sparsehash,corburn/sparsehash,robertschrader/sparsehash,tgoodyear/sparsehash,JanX2/sparsehash,mrxsaimon/sparsehash,COMBINE-lab/sparsehash,StevenLOL/sparsehash,tcpan/sparsehash,lhigueragamboa/sparsehash,liuqiang2/sparsehash,aadityakalsi/sparsehash,StevenLOL/sparsehash,danielwhitehall/sparsehash,PanHao000/sparsehash,robertschrader/sparsehash,danielwhitehall/sparsehash,danielwhitehall/sparsehash,xtao/sparsehash,corburn/sparsehash,chengmo03013106/sparsehash,mikeagn/sparsehash,mrxsaimon/sparsehash,jacklicn/sparsehash,RChehowski/sparsehash,lukedeo/sparsehash,epitzer/sparsehash,sparsehash/sparsehash,lukedeo/sparsehash,JanX2/sparsehash,TomasRejhons/sparsehash,yuanjia1011/sparsehash,jbboehr/sparsehash,stephane-martin/sparsehash,blackball/sparsehash,leondutoit/sparsehash,pip010/sparsehash,rob-p/sparsehash,windeye/sparsehash,jbboehr/sparsehash,blackball/sparsehash,resouer/sparsehash,TomasRejhons/sparsehash,zegl/sparsehash,StevenLOL/sparsehash,kmammou/sparsehash,chengmo03013106/sparsehash,leondutoit/sparsehash,yuanjia1011/sparsehash,chengmo03013106/sparsehash,kmammou/sparsehash,JanX2/sparsehash,rob-p/sparsehash,gulgi/sparsehash,fritzo/sparsehash,felixguendling/sparsehash,COMBINE-lab/sparsehash,borud/sparsehash,zegl/sparsehash,sparsehash/sparsehash,kaka1992/sparsehash,epitzer/sparsehash,jbboehr/sparsehash,stephane-martin/sparsehash,aadityakalsi/sparsehash,rob-p/sparsehash,resouer/sparsehash,bufans/sparsehash,redknightlois/sparsehash,tcpan/sparsehash,kmammou/sparsehash,lhigueragamboa/sparsehash,PanHao000/sparsehash,leondutoit/sparsehash,WangDequan/sparsehash,xinchoubiology/sparsehash,gulgi/sparsehash,yuanjia1011/sparsehash,bufans/sparsehash,redknightlois/sparsehash,kinjalbhavsar/sparsehash,borud/sparsehash,redknightlois/sparsehash,epitzer/sparsehash,pip010/sparsehash,TomasRejhons/sparsehash,COMBINE-lab/sparsehash,fritzo/sparsehash,PanHao000/sparsehash,WangDequan/sparsehash,resouer/sparsehash,mikeagn/sparsehash,lukedeo/sparsehash,pip010/sparsehash,mrxsaimon/sparsehash,guiquanz/sparsehash,felixguendling/sparsehash,sparsehash/sparsehash,kaka1992/sparsehash,xtao/sparsehash,gulgi/sparsehash,xinchoubiology/sparsehash,zegl/sparsehash,lhigueragamboa/sparsehash,kinjalbhavsar/sparsehash,aadityakalsi/sparsehash,kaka1992/sparsehash,liuqiang2/sparsehash,tgoodyear/sparsehash,WangDequan/sparsehash,corburn/sparsehash,RChehowski/sparsehash,stephane-martin/sparsehash,tcpan/sparsehash,venkey-ariv/sparsehash,guiquanz/sparsehash,venkey-ariv/sparsehash,xtao/sparsehash,dabbertorres/GoogleHashMaps,xinchoubiology/sparsehash,dabbertorres/GoogleHashMaps,felixguendling/sparsehash,windeye/sparsehash,tgoodyear/sparsehash,blackball/sparsehash,windeye/sparsehash,jacklicn/sparsehash,fritzo/sparsehash,robertschrader/sparsehash,jacklicn/sparsehash,mikeagn/sparsehash,venkey-ariv/sparsehash,borud/sparsehash,bufans/sparsehash