[NEW TYPE INFERENCE] Fix bug in GlobalTypeInfo#getScopeHelper, so that local variables shadow outer functions correctly.

(Also, don't create a DeferredCheck that is never used.)

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71204077
Translate ES6 module syntax to CommonJS syntax
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71207284