Allow --language_in flag to be ES6 or ES6_STRICT.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65484235
Convert many tail-recursive methods to use while loops
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65534269
[NEW TYPE INFERENCE] Infer types for @const vars/props where possible.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65538592
Add @jaggerPromise annotation which will be used to implement
asynchronous provide.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65541018
Convert final entryset capable loop
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65544992
ES6: Add the ability to create Nodes for functions with default parameters.

Part of issue 1102.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65548538
Moar whitespace!
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65551511
Use Throwables.propagate instead of constructing a new RuntimeException.

This provides more useful stack traces when an error is thrown.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=65552365