Add support for throw statements inside generator functions.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72564942
Separated logic for determining whether control leaves a statement early into a separate traversal.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72585810