Allow proper inlining of aliases of classes with "goog.addSingletonGetter" calls.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=51558252
Move variable redeclaration check from SyntacticScopeCreator to VarCheck.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=51577979
Remove warnings for unknown parameter type and unknown return type in extern
exports pass.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=51612072