sp
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66825469
Remove unused code in CompilerOptions.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66826248
If we see ES6-only code while parsing, convert the parser warning to an error, so that we don't try to pass ES6 code to other compiler passes which don't know how to handle it.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=66830665