Fixing STRONG_MODE_COULD_NOT_INFER violations before they fail _analyze targets.
Fixing STRONG_MODE_COULD_NOT_INFER violations before they fail _analyze targets.

Tested:
    TAP --sample for global presubmit queue
    http://test/OCL:137793325:BASE:137790237:1477983295463:16baf0c8

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=137825200

dart-lang/intl