Handle InternalError as failures

These are printed by glcts udner some circumstances, and not handling them causes this assertion to fail:

deqp-runner: ../src/deqp-runner.cc:544: bool process_block(Context&, unsigned int, unsigned int): Assertion `tests.size() == results.size()' failed.

Signed-off-by: Tomeu Vizoso tomeu.vizoso@collabora.com