Add assert for unexpected syntaxkind and a conservative temporary fix. #2218
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Conservative fix for a crash in the navbar and adding instrumentation for a better fix.
TypeError: Unable to get property 'localeCompare' of undefined or null reference
at Anonymous function (:20435:25)
at sortNodes (:20433:17)
at getChildNodes (:20424:17)
at createSourceFileItem (:20639:21)
at createTopLevelItem (:20601:25)
at getItemsWorker (:20491:21)
at getNavigationBarItems (:20379:13)
at getNavigationBarItems (:26732:13)
at Anonymous function (:28077:17)
at simpleForwardCall (:27843:9)
at forwardJSONCall (:27857:13)
at forwardJSONCall (:27888:13)
at getNavigationBarItems (:28076:13)