Parse array patterns in var and assign statements.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=67875851
Add support for ES6 rest parameters.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=67884589
Use "call" instead of "apply" in transpilation of rest parameter
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=67885192
[NEW TYPE INFERENCE] Allocate fewer strings in FunctionType.toString
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=67904344
[NEW TYPE INFERENCE] Replace recursive toString() calls with appendTo(StringBuilder)

Also fix toString result for "function()"
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=67982701