Add covariance related files to the android build.
Add covariance related files to the android build.

Change-Id: Ica8bf2b28bcbf6cde338f9ca3c64cd8a7d968a4c

ysonggit/ceres-solver,DougFirErickson/ceres-solver,DougFirErickson/ceres-solver,ysonggit/ceres-solver,whuaegeanse/ceres-solver,whuaegeanse/ceres-solver,DougFirErickson/ceres-solver,DougFirErickson/ceres-solver,whuaegeanse/ceres-solver,ysonggit/ceres-solver,ysonggit/ceres-solver,whuaegeanse/ceres-solver