Make ModuleAdapters stateless.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=54155756
Fix test to conform with stateless module adapters.
Revert a conversion from an array to a list (to avoid the extra unnecessary allocations) and deal with a few code review nits.
Merge pull request #335 from cgruber/statelessmodules

Make ModuleAdapter implementations stateless (incompatible codegen change)