fix a problem that class loasing/unloading after warm-up is counted when auto-mode
fix a problem that class loasing/unloading after warm-up is counted when auto-mode

git-svn-id: c108d6bd3f0d9e1e482bf6e2c3e4c17568ceb8cf@55 de1aa1df-9997-7042-bcab-4b162ccbf486

gperfutils/gbench