Fix bug with parser state when using vtop

[Tyriar]

Fixes #662

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See the comment in code for an explanation, I couldn't figure out the root cause but after Parser.parse finished, the state of it would reset. Interestingly, this works:

var state = this.parser.parse(data);
this.parser.setState(state);

Where this does not:

this.parser.setState(this.parser.parse(data));

[coveralls]

Coverage increased (+0.01%) to 69.002% when pulling 2c3d98a on Tyriar:662_parser_state_hack into 35b32b7 on sourcelair:master.