Automatic cleanups in rhino_ast.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81680805
Move the EnumSet containing just TokenType.EQUAL into a static variable, to avoid calling EnumSet.of() multiple times.

When parsing a large deps.js file, EnumSet.of() is about 6% of the total parse time.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81682088
Fix jQuery.post type signature. success may be null, per
http://api.jquery.com/jQuery.post/.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81717130
[NEW TYPE INFERENCE] Do more strict checking when creating ObjectType
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81721227