Don't crash when an id generator doesn't have a parameter, report an error instead.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=59275085
Remove unused imports
[NEW TYPE INFERENCE]

Handled the in operator, property deletion, +=, switch, try/catch/finally, regexp literals, array literals.

With this change we should be done with the core language.
Major features left: generics, Closure-library-specific constructs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=59338053