Refactoring parse_request to unify returning path
Refactoring parse_request to unify returning path

Review URL: http://codereview.appspot.com/4977042
google/pywebsocket,GoogleChromeLabs/pywebsocket3,google/pywebsocket,googlearchive/pywebsocket,google/pywebsocket,GoogleChromeLabs/pywebsocket3,GoogleChromeLabs/pywebsocket3,googlearchive/pywebsocket,googlearchive/pywebsocket