Lever not assigned in Writer via custom LogMessage

[abumq]

This issue was originally noticed in residue logging server. Code here

Basically, in Writer construction with custom LogMessage, m_level is not assigned, as a result level's enabled/disabled state is dependent upon undefined behaviour.

Writer(LogMessage* msg, base::DispatchAction dispatchAction = base::DispatchAction::NormalLog) :
    m_msg(msg), m_line(0), m_logger(nullptr), m_proceed(false), m_dispatchAction(dispatchAction) {
  }

This is ignored as a result of this

m_proceed = m_logger->enabled(m_level) 

We need to assign anything that is available in msg as long as they're valid values, especially m_level as it's checked at construct