Document the behavior of ignoring duplicate installations of the same module instance. Nit: invert an if statement.
Document the behavior of ignoring duplicate installations of the same module instance.
Nit: invert an if statement.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=308673499

google/guice,mcculls/guice,google/guice,mcculls/guice,mcculls/guice,google/guice