Fix uninitialized MsgStream member.
Compare changes
@@ -44,6 +44,7 @@ MsgStream::MsgStream(IMessageSvc* svc, int)
@@ -55,6 +56,7 @@ MsgStream::MsgStream(IMessageSvc* svc, std::string source, int)
Member MsgStream::m_currLevel was not initialized in the constructors.
Causes warnings from the undefined behavior sanitizer.