Use #ifdef to protect calling Factorial in benchmark_test.cc
Use #ifdef to protect calling Factorial in benchmark_test.cc

quantumsteve/benchmark,subailong/benchmark,xlqian/benchmark,chandlerc/benchmark,nickhutchinson/benchmark,eliben/benchmark,quantumsteve/benchmark,Photonomie/benchmark,efcs/benchmark,disconnect3d/benchmark,disconnect3d/benchmark,fuchsia-mirror/third_party-benchmark,google/benchmark,ntx-/benchmark,nickhutchinson/benchmark,mockingbirdnest/benchmark,codygray/benchmark,bowlofstew/benchmark,chandlerc/benchmark,efcs/benchmark,nickhutchinson/benchmark,bowlofstew/benchmark,mockingbirdnest/benchmark,gezidan/benchmark,subailong/benchmark,chemhack/benchmark,eliben/benchmark,nickhutchinson/benchmark-cxx03,quantumsteve/benchmark,xlqian/benchmark,quantumsteve/benchmark,ntx-/benchmark,codygray/benchmark,chemhack/benchmark,bowlofstew/benchmark,eliben/benchmark,disconnect3d/benchmark,fuchsia-mirror/third_party-benchmark,everbase/benchmark,LepelTsmok/benchmark,chandlerc/benchmark,google/benchmark,eliben/benchmark,everbase/benchmark,subailong/benchmark,bowlofstew/benchmark,ntx-/benchmark,mockingbirdnest/benchmark,LepelTsmok/benchmark,Photonomie/benchmark,everbase/benchmark,gezidan/benchmark,fuchsia-mirror/third_party-benchmark,efcs/benchmark,nickhutchinson/benchmark-cxx03,chandlerc/benchmark,nickhutchinson/benchmark,codygray/benchmark,chemhack/benchmark,ntx-/benchmark,Photonomie/benchmark,xlqian/benchmark,Photonomie/benchmark,disconnect3d/benchmark,nickhutchinson/benchmark-cxx03,chemhack/benchmark,mockingbirdnest/benchmark,LepelTsmok/benchmark,google/benchmark,LepelTsmok/benchmark,nickhutchinson/benchmark-cxx03,efcs/benchmark,fuchsia-mirror/third_party-benchmark,everbase/benchmark,xlqian/benchmark,subailong/benchmark,gezidan/benchmark,gezidan/benchmark,codygray/benchmark