ES6: Add support for arrow functions in the AstValidator.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66556204
Add recently introduced parameter to app.window.show method.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66591813
Update obsolete postMessage arguments, tighten nullability, and add global
version.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66618698
Add a unit test to show that base.js is sorted correctly despite not having a goog.require or goog.provide.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66624516
Change the meaning of "isEquivalentToShallow" so it simply means don't recurse to children. Move the special function logic to NodeUtil.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66647403
Transpile arrow functions into standard ES3 functions.

See issue #406.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66653799
Adds templating to HTML5 MessageEvent extern.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66667084
Minor cleanup of the options setting heirarchy.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66684885