Fix Windows build break.
Fix Windows build break.

Change-Id: I8b2b4c795429fd10ceeff83016825f1a9a8e305d

techoe/ceres-solver,caomw/ceres-solver,arnaudgelas/ceres-solver,vedanshu95/ceres-solver,vedanshu95/ceres-solver,kartikkumar/ceres-solver,jmwalls/ceres-solver-fork,timfel/ceres-bin,entylop/ceres-solver,timfel/ceres-bin,ikoruk/ceres-solver,ysonggit/ceres-solver,techoe/ceres-solver,stonier/ceres_solver,ikoruk/ceres-solver,whuaegeanse/ceres-solver,jmwalls/ceres-solver-fork,ikoruk/ceres-solver,DougFirErickson/ceres-solver,jmwalls/ceres-solver-fork,stonier/ceres_solver,caomw/ceres-solver,whuaegeanse/ceres-solver,DougFirErickson/ceres-solver,arnaudgelas/ceres-solver,vedanshu95/ceres-solver,DougFirErickson/ceres-solver,entylop/ceres-solver,kartikkumar/ceres-solver,DougFirErickson/ceres-solver,whuaegeanse/ceres-solver,stonier/ceres_solver,pritasam/ceres-solver,timfel/ceres-bin,pritasam/ceres-solver,ikoruk/ceres-solver,kartikkumar/ceres-solver,timfel/ceres-bin,kartikkumar/ceres-solver,caomw/ceres-solver,jmwalls/ceres-solver-fork,pritasam/ceres-solver,techoe/ceres-solver,ikoruk/ceres-solver,whuaegeanse/ceres-solver,entylop/ceres-solver,arnaudgelas/ceres-solver,stonier/ceres_solver,ysonggit/ceres-solver,ysonggit/ceres-solver,entylop/ceres-solver,ysonggit/ceres-solver