Force --yes to mod_image_for_test.sh call.  archive_build.sh runs non-interactive most of the time.
Force --yes to mod_image_for_test.sh call.  archive_build.sh runs non-interactive most of the time.

Review URL: http://codereview.chromium.org/661151

nicescale/scripts,endocode/scripts,nicescale/scripts,vmware/coreos-scripts,vmware/coreos-scripts,zhang0137/scripts,fivethreeo/scripts,mischief/scripts,mjg59/scripts,bcwaldon/coreos-scripts,sigma/coreos-scripts,marineam/coreos-scripts,gtank/scripts,coreos/scripts,glevand/coreos--scripts,mischief/scripts,nicescale/scripts,andrejro/coreos--scripts,crawford/scripts,endocode/scripts,sigma/coreos-scripts,mischief/scripts,crawford/scripts,fivethreeo/scripts,marineam/coreos-scripts,gtank/scripts,bcwaldon/coreos-scripts,trnubo/scripts,smilart/scripts,smilart/scripts,BugRoger/scripts,glevand/coreos--scripts,trnubo/scripts,andrejro/coreos--scripts,fivethreeo/scripts,zhang0137/scripts,vmware/coreos-scripts,BugRoger/scripts,mjg59/scripts,smilart/scripts,mjg59/scripts,BugRoger/scripts,endocode/scripts,sigma/coreos-scripts,crawford/scripts,coreos/scripts,andrejro/coreos--scripts,trnubo/scripts,zhang0137/scripts,gtank/scripts,marineam/coreos-scripts,bcwaldon/coreos-scripts