We should not check if the mux framework internals work as expected in every handler.
The missing parameter error doesn't make sense from the user point of view.
This change initializes a proper vars context if the mux fails to do so and delegates
specific parameter error checks to the handlers.
Signed-off-by: David Calavera <david.calavera@gmail.com>
Upstream-commit: 389ce0aae6a303660e591ef80272322ac82854e2
Component: engine
f38f3109c2