Fix a bug when no var is synthesized for arguments.

Move the check for "arguments" to only guard error reporting,
not the var synthesis.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53821358
"@const @type {type}" -> "@const {type}"

JSDoc annotations can not be horizontally stacked when they are the second annotation is interpreted as comment. However, both @private and @const can declare a type so a separate annotation is not needed.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53838628
Resolve template types when a concrete subtype has templatized super class or implements a templated interface.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=53861826