Fix use of uninitialized arrays.

gradient_checking_cost_function_test.cc was using arrays without initializing
them which triggers valgrind errors, and causes failures when built on the N900.

Thanks to Sebastian Koch for reporting the error and Markus Moll for pin pointing
the cause of the error.

Change-Id: Iee498969bb5026eb302ea2990edf189e70f97800
1 file changed