[NEW TYPE INFERENCE]

Handle CAST nodes.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=61841342
Provide more useful errors if there is a type mismatch where several fields are identical.

Fixes issue 719.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=61843188
Externs version rollover dance for Maps API V3.16
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=61856486
Warn if a @const property or @const name defined in externs is assigned a value.

Fixes issue 1219.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=61892013
[NEW TYPE INFERENCE]

Migrate from substitution-based generics for nominal types to environment-based.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=61898351