Make the parameters to assertSameElements non-nullable.
Make the parameters to assertSameElements non-nullable.

RELNOTES[INC]: assertSameElements no longer accepts nulls

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=229759723

lucidsoftware/closure-library,google/closure-library,lucidsoftware/closure-library,lucidsoftware/closure-library,google/closure-library,lucidsoftware/closure-library,google/closure-library,google/closure-library,google/closure-library