Fix build issue with CUDA testing targets when compiling without gflags. Change-Id: I926a85c30b51802a99161679cb2a28fda6e3ef47
Ceres Solver is an open source C++ library for modeling and solving large, complicated optimization problems. It is a feature rich, mature and performant library which has been used in production at Google since 2010. Ceres Solver can solve two kinds of problems.
Please see ceres-solver.org for more information.