Fix tests by re-adding a Random() function, now properly implemented using RandomEngine().
Fix tests by re-adding a Random() function, now properly implemented using
RandomEngine().

petewarden/gemmlowp,petewarden/gemmlowp,maciekcc/gemmlowp,google/gemmlowp,google/gemmlowp,google/gemmlowp,petewarden/gemmlowp,maciekcc/gemmlowp,maciekcc/gemmlowp,google/gemmlowp,petewarden/gemmlowp