Fix in object pattern parsing to allow anything that is valid as the left side of an assignment, on the right side of a colon in an object pattern.

This is a roll-forward, but with some refactoring so that speculative parsing will fail faster, which prevents parsing of large object literals from taking a ridiculously long time.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76126495
Allow transpilation for --language_out=ES5 as well as ES3

Fixes #550
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76128389
Remove Event.prototype.state

I couldn't find this in any spec, and this definition conflicts
with that of subtype PopStateEvent.prototype.state
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76166119
Update the type of the "Object" function to indicate that it returns an Object if not called as a constructor.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76177522
Add a diagnostic group for conformance tests so they can be promoted to error
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76196359
A few small cleanups related to modules:

- Make sure errors are reported, not just created.
- Fix some broken targets due to missing BUILD deps
- Add more parser tests, and simplify the code printer tests
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=76206119