absltest doesn't set up test filtering and fail fast correctly when argv= is explicitly passed to absltest.main

[bhack]

Mentioning @yilei from #128 (comment):

I currently think it makes sense for absltest to merge the updated argv with the user specified one from kwargs,

/cc @haifeng-jin

[yilei]

Correction from #128 (comment):

Ah, since kwargs['argv'] always overrides argv in _run_and_get_tests_result, we should add filtering flags to kwargs['argv'] if present.