Background: The bridge is designed to leverage the Faces view state management
where ever possible. However, because a portlet may be re-rendered multiple
times before the next action is submitted, the bridge needs a way to
reference/restore this view state without relying on it (or its key) being
submitted in the request. To do this the bridge manages within its request
scope the value stored in the VIEW_STATE_PARAM hidden field. Unfotrunately
there is no clean/spec defined way to extract this value. Currently the bridge
implements StateManager, overrides writeState, wraps the responseWriter and
parses the data written into the response to extract it.
Need: A cleaner/spec defined way to get this value.